Test Equipment Anonymous (TEA) group therapy thread

[Specmaster]

The replacement speaker arrived today, hoping to fit it in the car tomorrow. Had a rummage around in the garage for my riveting kits, disappointed as the rivets that pass through the speaker fixing holes are only 5 mm long and will not be long enough to attach the speaker to the door. So I had to pop onto Amazon and look for some that more suitable, found some that are 12 mm long, those will do the job OK. Then I tried to do one of the 5 mm rivets as a trail and was amazed at just hard they were to do and thinking about doing 12 mm and 6 of them made me think about it and I just pulled the trigger on a neat attachment for cordless drill for riveting, both the gun and rivets should here today (Wednesday). Just hope that both come at the same time and from 2 deliveries.

I admire your desire to "keep it original", but I'll say this once: self tapping sheet metal screws are your friend. Especially when you're installing used speakers with a plastic frame which may have suffered embrittlement from age.

It is not booty-fab; it is the normal way professional car audio installers do it, and it is how the manufacturers used to do, before it was cheaper to use pop-rivets that were only cheaper because made with slave labor.

mnem
moo...?

I did think about using screws but dismissed it at for now, as the holes in the door are larger than those in the speaker, so I'd have to rotate the speaker, then the splash cover wouldn't do its job, the drainage point would be too high and risk creating a little pool if water did ingress into the door and the speaker lead would have to be lengthened in order to plug it into the socket on the speaker, so it might be easier and quicker to rivet it in the original location. I don't think the plastic has embrittled with age, it's the wrong type of plastic.

I did also consider using rivet nuts, which would make any future work on the speaker a doddle, but by then I'd already reassembled the door trim, so I was not able to measure the hole diameter in the door, so I chucked that thought out. If it goes south tomorrow, I'll have to resort to the self tappers and do the extra bits to make it work, but I think the rivets is the best way forward, especially with it being the woofer, this stereo has some kick arse bass on it and the screws may back themselves out with the vibrations.

[Specmaster]

<snip>
So I am over the moon, can't believe I got one of these for only 105 Euros ! 

It's a tremendous update over my old analog Philips. Much better rise time, frequency and amplitude are much more stable, 15MHz vs 1Mhz, GPIB for automation. Extra wave forms like saw tooth. Does noise generation, and arbitrary wave forms. Digital controls to set the frequency in steps, that's convenient for testing stuff and plot frequency responses. The ability to vary the frequency from super low up to the max 15MHz with NO interruption, no decade switch to fuck with, is also incredible, love it.

Time base most likely better too. At the back it says " Option 001 ". I assume it's the crappiest option but still better than the Philips for sure. Plenty good enough for what I do. PLUS, I really don't care anyway because it has an external 10MHz ref input so that's what I plan on using anyway, if I ever want great accuracy.

So that's it... was unexpected, was just pot luck, but here I am modernizing the lab !

See Tautech ? Now I don't want to hear you anymore saying I only buy old junk. I am a modern HP guy now. Less vacuum tubes and more CPU's.
Of course I am keeping the old Philips, love it, and was given by my dad, it's sentimental, my first sig gen. I will never part with it.


First attached pic is the one I asked the seller to do. Others are from me.

Nice score, but maybe you should have made a low ball offer on the scope as well, what did you have to lose?

Zero money ! As cheap as 105 Euros was for that sig gen, I do not have any money. I now need to quickly fix and sell a couple scopes that have been waiting on the shelves for months, to pay for the sig gen.

The scope vaguely tempted me, still for sale BTW been sold now it appears :

https://www.leboncoin.fr/bricolage/2150494690.htm

It's a "Megazoom" version which Dragon is all excited about and am now kinda curious about... and it costs only 50 Euros.

But... it's an Agilent rebrand / facelift. I absolutely despise this industrial design. Looks so cheap and ugly, I absolutely refuse to own these things. It's only 60MHz. It's heavily yellowed. There is a missing button below the CRT.

I DO want an old Megazoom, but a proper HP one, I love those, but also at least 100MHz, not yellowed and no broken/missing knobs.

Buying it to flip it wouldn't have worked either, because I can't afford to buy / spend now, and wait for 6 months to get my money back.
Plus given all I said above, this scope would be very difficult to resell, here anyway... and if it does sell it would be for the same price I paid for it, tops.

This scope makes no sense either for me to use, or to buy to flip. I try now try to be less impulsive and more reasonable, because of lack of space and money.

I admire your resistance, I would have gone out on a limb for that scope personally, even with the missing button, which I think is a rubberised thing with a carbon pad that I'm sure could be bodged or resolved, even it meant sticking a small push button somewhere, its only used via the on-screen menu system, so no real biggy to overcome. As you say, its sold now, that tells you that it was a real bargain if it was listed at 50 Euros, you more than likely would have secured it for a low ball offer of 40 Euros and sold it on for far more 

Scopes don't sell here atm. 50 Euros is for a clean working good condition one.  Anything above 50 euros is impossible to sell quickly.
Had I bought it, the best I could have gotten for given its condition, would be 75 euros, it I am lucky. Waiting months and month to make 10 or 20 euros profit a 50 Euros or so buy, is not worth the time and initial investment.

I don't have money to burn nor space to buy old clunky stuff hoping to maybe make 10 or 20 Euros profit on them.

Scope sell for dirt cheap, working, and in good nick. So one in not so good shape like this one, either you buy it because like Dragon or you, you like it and are happy using it as is, or, if you want to make a profit on it, then you must get it for free or almost (you have to factor in shipping as well).

for example I bought for 6 Euros SHIPPED, and old brown Philips scope. it's in good shape and dual time base. I know if I can fix it I could get maybe 75 Euros for it. That's about worth me putting a few hours fixing it. Also my 4 channel GOULD 1604 analog+digital scope with built-in printer, I know this one can sell for 75 or 100 Euros maybe (I fixed and sold a 1604 withOUT printer ) for 120 Euros, miracle.
I paid 20 euros for it IIRC, very cheap anyway. So I know I have a reasonable chance of making a few bucks if I can fix it.

But generally speaking, at least here, I don't live else where sorry, it's generally not worth buying with the intent of reselling for a profit. I have eventually realized this an have now stopped wasting my time with this, it's just not worth the trouble and time fixing the things.  Return on investment (time, storage, hours spent on it, effort...) is just not worth it, at all.

Wow scopes are really cheap over there then, here the going rate for old analogue cro's is still around £1 a MHz but that scope was digital with all the measurement capability as well as being a mixed signal scope which are worth more, if only the bleeding shipping costs weren't stupidly high because of the bleeding B word 

[Cerebus]

You two need to consider this. Only $122/night. Split the cost and hash it out once and for all.



Ain't I a stinker? 

Too colourful. Try this:

Or this:



"The owls are not what they seem."

[Vince]

Wow scopes are really cheap over there then, here the going rate for old analogue cro's is still around £1 a MHz but that scope was digital with all the measurement capability as well as being a mixed signal scope which are worth more, if only the bleeding shipping costs weren't stupidly high because of the bleeding B word 

Yeah this Agilent was a better bang for buck than the average junk I see all day long on leboncoin.fr , for sure, not saying otherwise... and I did say, or did I, that I was indeed tempted, briefly.. then reconsidered my position based on everything I have already said. The me of 4/5 years ago would have bought it probably... but that me is no more. I have to be more choosy now. I am already completely overwhelmed by my stock of TE 

Well at least I did take note that this model scope was very appreciated even in this condition and even with the ugly agilent styling. So... if I come across anotyher one I will try to think of posting it here in case someone wants it.

[factory]

Who was it that wanted a 5245L counter?
One on ePay.de at the moment, the asking price is almost back to what they were before TSP video and no ancient oval connector to worry about. 

https://www.ebay.de/itm/275290271369



And for those in the UK, a Racal frequency meter good for +500MHz, looks in much nicer condition than the wreck I repaired.
https://www.ebay.co.uk/itm/255508260812



David

[Vince]

Nixie DMM... Tek 180A, Tek RM17.... I al going well. I am getting confident at fixing these things, they don't scare me as much any more.... so I decided this evening to start work on a fourth piece of vintage TE. My HP 120B scope. I have already presented this one when I got it some months ago... uh let me look at my notes... oh boy that was just one YEAR ago now, time flies !

It's about time I work on it ! 

So as a remiinder, the story goes like this :

Not really into HP scopes other than the 54XXX series, but I stumbled upon this one on my daily scope search. It was FREE ! So... that caught my attention. 
I looked at the pics...I somehow found it cute, it was in good nick, it was an HP not some random junk... so I fell for it, I was weak.
Seller did say it was free because he stole all the tubes from it. He didn't want to ship it at first, but I insisted and finally convinced him.

Other than the CRT and HV rectifiers along with it, there are 17 tubes in this thing. Well good news is, not ALL have been scavenged. 6 are still in the scope.
Guy only stole the ones that audiophools tend to like : the 6DJ8 and 12Axx .  Still, that's 11 tubes missing in all. Luckily these are very common in Tek scopes, so I have many of them, not a problem, cost me nothing.  The 6U8 are also missing, that's more annoying as tehre are zero of them in my 20+ collection of Tek scopes ! Sucks 
Luckily I found at the time, some Russian Ebay seller that was selling like 12 or 16 NOS of them for only 12 Euros or something, with just one caveat : ad said the tubes had ZERO markings on them... clean glass. Hmmm.... still was too good to pass, so I fell for it. To my surprise I DID receive all these tubes, the guy did not just disappear with my money !   
They indeed look brand new. Indeed no markings. However I compared them with pics I could find online, and the internals of the tubes appear to match... so MAYBE, just maybe... they are indeed 6U8 and maybe one or two of them actually works. We shall see.


Anyway. scope is in great shape inside out. Inside no corrosion, just lots of cooed black dust on the wiring harnesses and HV / power supply components. But otherwise it looks in excellent shape.
I got my ... ZERO Euro worth here for sure !

So first, a food clean, should be quick.

Then take apart a few Tek scopes to get all the tubes I need.

The replace the two 40uF axial caps  in the trigger switch assembly,that are done for. However according to the schematics, I can work on the scope without these caps, for they are used to select the Auto or Norm trigger mode, with the caps being shorted in Auto mode. So well I can just removed them and short the pins and bob's your uncle.

So that's what I am gonna do...

Stay tuned 

[dl6lr]

Oh, don't get us started on scope/DMM probes. They cost more than the instrument

Well, this applies to RF power sensor heads too...

Latest score:

2 Tek P6053B with accessories
1 Tek P6056 plus spare tip
1 Tek P6057 plus spare tip

And a Tek 1240 LA with manual, probes and a 64K RAM module for free, just have to fix it.

[Vince]

Who was it that wanted a 5245L counter?
One on ePay.de at the moment, the asking price is almost back to what they were before TSP video and no ancient oval connector to worry about. 

https://www.ebay.de/itm/275290271369

David

Was MEEEEEE !!!!

Hmmm... 125 Euros BIN.. reasonable indeed... But too much for me right now 

Especially since it comes with zero plugins.

Later for sure... there will be more for sale.

For now, I have its French counterpart my Ferisol counter, I am happy with it, loving it 

[mnementh]

I really think that things like a missing button or yellowing are really poor excuses to use here,

mnem
 

"Excuses" ? I don't have to give any excuse for not liking or wanting this particular scope. I don't want it, period. I have givne my reason, if any were needed. you don't find them valid in your eyes, that's fine, your are not god, I don't need your approval to make my choices 
Just like you don't need my approval for anything you buy 

in this little corner of the internet. And hating on it cuz Keysight is just bizarre. IMHO.

That's industrial design for you.. you don't seem to be affected by industrial design or cosmetic condition or even missing or broken controls. Well, I am.   

As long as I have a choice between two or more products that meet my needs, I will chose the one I like the design of best. Doing otherwise would be strange, why would I purposefully buy something I find crap cheap and ugly, and have it ruin my daily lab experience, if I can get a similar product but better that I like much better ?! 

Vince, it has nothing to do with any of that.

What do you have that's a more capable scope, and why do you think it is?

mnem
*toddles off to make some too-long bolts shorter*

[med6753]

Nixie DMM... Tek 180A, Tek RM17.... I al going well. I am getting confident at fixing these things, they don't scare me as much any more.... so I decided this evening to start work on a fourth piece of vintage TE. My HP 120B scope. I have already presented this one when I got it some months ago... uh let me look at my notes... oh boy that was just one YEAR ago now, time flies !

It's about time I work on it ! 

So as a remiinder, the story goes like this :

Not really into HP scopes other than the 54XXX series, but I stumbled upon this one on my daily scope search. It was FREE ! So... that caught my attention. 
I looked at the pics...I somehow found it cute, it was in good nick, it was an HP not some random junk... so I fell for it, I was weak.
Seller did say it was free because he stole all the tubes from it. He didn't want to ship it at first, but I insisted and finally convinced him.

Other than the CRT and HV rectifiers along with it, there are 17 tubes in this thing. Well good news is, not ALL have been scavenged. 6 are still in the scope.
Guy only stole the ones that audiophools tend to like : the 6DJ8 and 12Axx .  Still, that's 11 tubes missing in all. Luckily these are very common in Tek scopes, so I have many of them, not a problem, cost me nothing.  The 6U8 are also missing, that's more annoying as tehre are zero of them in my 20+ collection of Tek scopes ! Sucks 
Luckily I found at the time, some Russian Ebay seller that was selling like 12 or 16 NOS of them for only 12 Euros or something, with just one caveat : ad said the tubes had ZERO markings on them... clean glass. Hmmm.... still was too good to pass, so I fell for it. To my surprise I DID receive all these tubes, the guy did not just disappear with my money !   
They indeed look brand new. Indeed no markings. However I compared them with pics I could find online, and the internals of the tubes appear to match... so MAYBE, just maybe... they are indeed 6U8 and maybe one or two of them actually works. We shall see.


Anyway. scope is in great shape inside out. Inside no corrosion, just lots of cooed black dust on the wiring harnesses and HV / power supply components. But otherwise it looks in excellent shape.
I got my ... ZERO Euro worth here for sure !

So first, a food clean, should be quick.

Then take apart a few Tek scopes to get all the tubes I need.

The replace the two 40uF axial caps  in the trigger switch assembly,that are done for. However according to the schematics, I can work on the scope without these caps, for they are used to select the Auto or Norm trigger mode, with the caps being shorted in Auto mode. So well I can just removed them and short the pins and bob's your uncle.

So that's what I am gonna do...

Stay tuned 

Robbing vacuum tubes out of Tek scopes to fix an hp scope? Well.....OK.....just don't make a habit of it. 

[mnementh]

The replacement speaker arrived today, hoping to fit it in the car tomorrow. Had a rummage around in the garage for my riveting kits, disappointed as the rivets that pass through the speaker fixing holes are only 5 mm long and will not be long enough to attach the speaker to the door. So I had to pop onto Amazon and look for some that more suitable, found some that are 12 mm long, those will do the job OK. Then I tried to do one of the 5 mm rivets as a trail and was amazed at just hard they were to do and thinking about doing 12 mm and 6 of them made me think about it and I just pulled the trigger on a neat attachment for cordless drill for riveting, both the gun and rivets should here today (Wednesday). Just hope that both come at the same time and from 2 deliveries.

I admire your desire to "keep it original", but I'll say this once: self tapping sheet metal screws are your friend. Especially when you're installing used speakers with a plastic frame which may have suffered embrittlement from age.

It is not booty-fab; it is the normal way professional car audio installers do it, and it is how the manufacturers used to do, before it was cheaper to use pop-rivets that were only cheaper because made with slave labor.

mnem
moo...?

I did think about using screws but dismissed it at for now, as the holes in the door are larger than those in the speaker, so I'd have to rotate the speaker, then the splash cover wouldn't do its job, the drainage point would be too high and risk creating a little pool if water did ingress into the door and the speaker lead would have to be lengthened in order to plug it into the socket on the speaker, so it might be easier and quicker to rivet it in the original location. I don't think the plastic has embrittled with age, it's the wrong type of plastic.

I did also consider using rivet nuts, which would make any future work on the speaker a doddle, but by then I'd already reassembled the door trim, so I was not able to measure the hole diameter in the door, so I chucked that thought out. If it goes south tomorrow, I'll have to resort to the self tappers and do the extra bits to make it work, but I think the rivets is the best way forward, especially with it being the woofer, this stereo has some kick arse bass on it and the screws may back themselves out with the vibrations.

I was thinking more about the assache if you decide you don't like the way it sounds... and you can't really tell how it's gonna sound until it's all together and the door skin back on...

   And sorry; I take for granted that anybody can lay hands on these, as they're a standard hardware store item over here from the Hillman drawers in a variety of sizes and depths. Also SOP for car audio installers; certain kits of speakers even come with them standard. 

Here's hoping the assache was worth it, and you only have to do it once. 

mnem
 

[duckduck]

I was looking for info on my Lambda LQD-421. I think that's what it is. It's on the other side of the room and I can't be bothered. I found some info on this nice little site:

https://djerickson.com/

He mentioned the HP 3466A and it seemed interesting: auto-ranging, 7-segment LED display, measures 1200V DC. I hopped on ebay and bought a used one for cheap. Unfortunately, it displays OL no matter what is measured. Seller promises to issue a refund, and says I can keep the unit. I cracked it open and don't see any obvious problems. I had to cut through a cal sticker to split the clamshell, that's a good sign that nobody's been in there, "fixing". This model does indeed have a sealed lead acid battery and associated charging circuit mounted to the inside of the case lid. Neat. I'm afraid that this unit is going to go on to The Shelf Across The Room™ until free time and motivation join forces. I'm meeting with an architect next week who is going to help me design my Garage Mahal, DV. Looking forward to that.

Operating and service manual here:

https://www.keysight.com/us/en/product/3466A/4-12-digit-dmm.html#resources

EDIT: The HP 3466A was sold as "Used".

EDIT EDIT: I removed the SLA battery for storage. I don't imagine that sulfuric acid dripping on the main PCB would make repair any easier.

EDIT^3: Date codes mark this unit as having been born in late 1984. I measured the 6V battery and it's a little flat, outputting only 1.8mV.

[Cubdriver]

I was looking for info on my Lambda LQD-421. I think that's what it is. It's on the other side of the room and I can't be bothered. I found info this nice little site:

https://djerickson.com/

He mentioned the HP 3466A and it seemed interesting: auto-ranging, 7-segment LED display, measures 1200V DC. I hopped on ebay and bought a used one for cheap. Unfortunately, it displays OL no matter what is measured. Seller promises to issue a refund, and says I can keep the unit. I cracked it open and don't see any obvious problems. I had to cut through a cal sticker to split the clamshell, that's a good sign that nobody's been in there, "fixing". This model does indeed have a sealed lead acid battery and associated charging circuit mounted to the inside of the case lid. Neat. I'm afraid that this unit is going to go on to The Shelf Across The Room™ until free time and motivation join forces. I'm meeting with an architect next week who is going to help me design my Garage Mahal, DV. Looking forward to that.

Operating and service manual here:

https://www.keysight.com/us/en/product/3466A/4-12-digit-dmm.html#resources

EDIT: The HP 3466A was sold as "Used".

Nice to see that the battery doesn't appear to have vomited corrosive juices everywhere - looks like a nice clean instrument.  Hopefully it will turn out to be a minor thing once you get into digging into it.

-Pat

[Cubdriver]

Nixie DMM... Tek 180A, Tek RM17.... I al going well. I am getting confident at fixing these things, they don't scare me as much any more.... so I decided this evening to start work on a fourth piece of vintage TE. My HP 120B scope. I have already presented this one when I got it some months ago... uh let me look at my notes... oh boy that was just one YEAR ago now, time flies !

It's about time I work on it ! 

So as a remiinder, the story goes like this :

Not really into HP scopes other than the 54XXX series, but I stumbled upon this one on my daily scope search. It was FREE ! So... that caught my attention. 
I looked at the pics...I somehow found it cute, it was in good nick, it was an HP not some random junk... so I fell for it, I was weak.
Seller did say it was free because he stole all the tubes from it. He didn't want to ship it at first, but I insisted and finally convinced him.

Other than the CRT and HV rectifiers along with it, there are 17 tubes in this thing. Well good news is, not ALL have been scavenged. 6 are still in the scope.
Guy only stole the ones that audiophools tend to like : the 6DJ8 and 12Axx .  Still, that's 11 tubes missing in all. Luckily these are very common in Tek scopes, so I have many of them, not a problem, cost me nothing.  The 6U8 are also missing, that's more annoying as tehre are zero of them in my 20+ collection of Tek scopes ! Sucks 
Luckily I found at the time, some Russian Ebay seller that was selling like 12 or 16 NOS of them for only 12 Euros or something, with just one caveat : ad said the tubes had ZERO markings on them... clean glass. Hmmm.... still was too good to pass, so I fell for it. To my surprise I DID receive all these tubes, the guy did not just disappear with my money !   
They indeed look brand new. Indeed no markings. However I compared them with pics I could find online, and the internals of the tubes appear to match... so MAYBE, just maybe... they are indeed 6U8 and maybe one or two of them actually works. We shall see.


Anyway. scope is in great shape inside out. Inside no corrosion, just lots of cooed black dust on the wiring harnesses and HV / power supply components. But otherwise it looks in excellent shape.
I got my ... ZERO Euro worth here for sure !

So first, a food clean, should be quick.

Then take apart a few Tek scopes to get all the tubes I need.

The replace the two 40uF axial caps  in the trigger switch assembly,that are done for. However according to the schematics, I can work on the scope without these caps, for they are used to select the Auto or Norm trigger mode, with the caps being shorted in Auto mode. So well I can just removed them and short the pins and bob's your uncle.

So that's what I am gonna do...

Stay tuned 

Robbing vacuum tubes out of Tek scopes to fix an hp scope? Well.....OK.....just don't make a habit of it. 

I'm hoping Vince actually means 'borrowing' the tubes from the Teks, and that once the HP is known to be operational he will buy it its own set of tubes...   

-Pat

[Specmaster]

@mnementh
I hope so too, the speaker is lighter than the old one but is mainly due to the far smaller magnet it uses, also the cone edge roll support is not as compliant, but either way it will sound way better than it currently does, although to be fair, nobody else has noticed the lack of bass in the car, thanks to the other three woofers. When it is fitted tomorrow morning, weather permitting, we will know the truth for sure. It would be nice if to fit the correct woofer back in the car if I come across another for sale in the UK. I know at the time when I put the cars' specification together for the company to order for me, the stereo upgrade was a significant increase in the overall cost, pushing the cost well over £32,000 9 years, which is now over £40,000 for the same kind of specification.

Yes, this was a lot more expensive to purchase at the time than other cars the company sourced for other staff members, who went for Audi A4 SE TDI, but because they were all leased, mine worked out the cheapest of the bunch, thanks to its far higher residual value at the end of the 3-year lease. So I kind of hit the jackpot there, I had a far better level of kit fitted than the others as standard, then I also added extras, while they had the standard models in order to creep under the monthly lease value limit. As a note of interest, at the time, there were 301 of my model car on the road and still as of this month 274 (91%) on the road in the UK as opposed to Audi, 13,869 then, now down to 9,608 (69%) on the road.

[Vince]

I really think that things like a missing button or yellowing are really poor excuses to use here,

mnem
 

"Excuses" ? I don't have to give any excuse for not liking or wanting this particular scope. I don't want it, period. I have givne my reason, if any were needed. you don't find them valid in your eyes, that's fine, your are not god, I don't need your approval to make my choices 
Just like you don't need my approval for anything you buy 

in this little corner of the internet. And hating on it cuz Keysight is just bizarre. IMHO.

That's industrial design for you.. you don't seem to be affected by industrial design or cosmetic condition or even missing or broken controls. Well, I am.   

As long as I have a choice between two or more products that meet my needs, I will chose the one I like the design of best. Doing otherwise would be strange, why would I purposefully buy something I find crap cheap and ugly, and have it ruin my daily lab experience, if I can get a similar product but better that I like much better ?! 

Vince, it has nothing to do with any of that.

What do you have that's a more capable scope, and why do you think it is?

mnem
*toddles off to make some too-long bolts shorter*

Nothing as of yet, hence why I did contemplate buying it, that plus the Megazoom thing that I was curious to experience as you were raving about it.
But, as I have said, using this scope is not the way I plan on acquiring the logic decoding capabilities.
I would not mind having serial decoding and stuff on a scope, but not on this particular scope.
I would be interested in having them in a fancy expensive modern scope like the R&S our German friend just acquired, for example, but even then, it still would not be in, replacement of a proper standalone logic analyzer. It would only be as a complement.

Any more questions ? 

[srb1954]

And a Tek 1240 LA with manual, probes and a 64K RAM module for free, just have to fix it.

Not an easy unit to fix as some of the circuitry is pretty difficult to access.

However, the main card cage does open up nicely to allow access to the logic boards, assuming you have the appropriate extender card.  Remember to supply an external fan to keep everything cool when you have it opened up for access.

Take care not to pinch any of the numerous ribbon cables when closing it up again. Ask me how I know!

[Specmaster]

I was looking for info on my Lambda LQD-421. I think that's what it is. It's on the other side of the room and I can't be bothered. I found some info on this nice little site:

https://djerickson.com/

He mentioned the HP 3466A and it seemed interesting: auto-ranging, 7-segment LED display, measures 1200V DC. I hopped on ebay and bought a used one for cheap. Unfortunately, it displays OL no matter what is measured. Seller promises to issue a refund, and says I can keep the unit. I cracked it open and don't see any obvious problems. I had to cut through a cal sticker to split the clamshell, that's a good sign that nobody's been in there, "fixing". This model does indeed have a sealed lead acid battery and associated charging circuit mounted to the inside of the case lid. Neat. I'm afraid that this unit is going to go on to The Shelf Across The Room™ until free time and motivation join forces. I'm meeting with an architect next week who is going to help me design my Garage Mahal, DV. Looking forward to that.

Operating and service manual here:

https://www.keysight.com/us/en/product/3466A/4-12-digit-dmm.html#resources

EDIT: The HP 3466A was sold as "Used".

EDIT EDIT: I removed the SLA battery for storage. I don't imagine that sulfuric acid dripping on the main PCB would make repair any easier.

EDIT^3: Date codes mark this unit as having been born in late 1984. I measured the 6V battery and it's a little flat, outputting only 1.8mV.

The 3466A is indeed a nice meter, I have had mine now for 5 years, and it is a reliable performer for sure it also of course has the unique feature of retaining a zero ohms adjustment pot which is accessible on the front panel by means of a terminal sized screwdriver. If you can source a replacement  SLA, I would recommend that, I replaced mine and on the rare occasions when you have power cuts, this meter will still be operational and of course, it is a portable 4.5 digit meter which can be extremely useful.

[Vince]

Robbing vacuum tubes out of Tek scopes to fix an hp scope? Well.....OK.....just don't make a habit of it. 

I'm hoping Vince actually means 'borrowing' the tubes from the Teks, and that once the HP is known to be operational he will buy it its own set of tubes...   

-Pat

Nope sorry, a tube is a tube.. a 6AU6 doesn't care if it's socketed inside a Tek or HP scope  ! 

Half my Tek scopes are donors, so they might as well save the life of an HP scope 

Anyway... BAD news....

I have just retrieved all the required tubes from a couple Tek scopes : x3 6DJ8 and x5 12AU7. Then I fitted also x3 6U8 from the 16 NOS I bought from Russia...

Scope powers up, no big bang nor smoke. Tubes light up, and "some light " on the CRT... cool 

However as I was playing with the controls to see what I could get out of the CRT, it soon became apparent that... the ONLY tube that I can't replace, the CRT... is FUCKED !!!!! 

How do I know you ask ? Good point... especially since I have never had a bad CRT so far ! So it's new to me..

I made a littel video of it 

Basically, the CRT is noisy. Yes, a CRT can make noises... it's blatant, not faint at all. My camera had no trouble capturing it.
It sounds like a metallic rattling noise inside the CRT, in the neck.... where all the plates and grids and all the delicate stuff is 

They are not vibrating of course.. instead I think they are arcing badly !

The thin metal parts inside must have got bent during shipping or damage prior to that I don't know, one of them must be too close to another, and it's arcing.

Using the CRT controls I can acutally kinda control this noise and turn the CRT into a musical instrument, no kidding ! Kinda fun... well not 
Using the brightness control I can make the noise louder or quieter, and the pitch go higher or lower.
Using the vertical or horizontal position controls, I can make the noise come and go at will --> as soon as I move the spot outside the screen, noise disappear. Put the spot back in the visible area, noise comes back...

Of course as it's arcing it makes weird things on the screen, as you can see. The frequency of the igh show on the screen, is 100% correlated with the noise/pitch of of the CRT neck.

I was so excited to fix it and have it all working nice and all... and it's dead 

Can one find a CRT for this scope these days ? Or one that would fit and be electrically compatible at least ? How expensive are they, if at all available ?
I rescued the scope because it's cute and was free.... I can't justify nor afford to put lots of money for a new CRT... that would need to get shipped of course so might be damaged as well when getting to me 

It's 00H36, I am about to go to bed... and I am very sad, I won't be making sweet dreams..... 

EDIT : the parts list in the manual says the CRT is " P31 PHOSPHOR INTERNAL GRATICULE " , part number 5083-0353

EDIT #2 : just google the P/N. It found one on Ebay USA, sold for .... 570 dollars ! for 450kHz CRT !!! 
Scope is a write off 

https://www.ebay.com/itm/274969806314

[med6753]

Yep, she's toast. 


Now put the tubes back. 

[Cubdriver]

Robbing vacuum tubes out of Tek scopes to fix an hp scope? Well.....OK.....just don't make a habit of it. 

I'm hoping Vince actually means 'borrowing' the tubes from the Teks, and that once the HP is known to be operational he will buy it its own set of tubes...   

-Pat

Nope sorry, a tube is a tube.. a 6AU6 doesn't care if it's socketed inside a Tek or HP scope  ! 

Half my Tek scopes are donors, so they might as well save the life of an HP scope 

Anyway... BAD news....

I have just retrieved all the required tubes from a couple Tek scopes : x3 6DJ8 and x5 12AU7. Then I fitted also x3 6U8 from the 16 NOS I bought from Russia...

Scope powers up, no big bang nor smoke. Tubes light up, and "some light " on the CRT... cool 

However as I was playing with the controls to see what I could get out of the CRT, it soon became apparent that... the ONLY tube that I can't replace, the CRT... is FUCKED !!!!! 

How do I know you ask ? Good point... especially since I have never had a bad CRT so far ! So it's new to me..

I made a littel video of it 

Basically, the CRT is noisy. Yes, a CRT can make noises... it's blatant, not faint at all. My camera had no trouble capturing it.
It sounds like a metallic rattling noise inside the CRT, in the neck.... where all the plates and grids and all the delicate stuff is 

They are not vibrating of course.. instead I think they are arcing badly !

The thin metal parts inside must have got bent during shipping or damage prior to that I don't know, one of them must be too close to another, and it's arcing.

Using the CRT controls I can acutally kinda control this noise and turn the CRT into a musical instrument, no kidding ! Kinda fun... well not 
Using the brightness control I can make the noise louder or quieter, and the pitch go higher or lower.
Using the vertical or horizontal position controls, I can make the noise come and go at will --> as soon as I move the spot outside the screen, noise disappear. Put the spot back in the visible area, noise comes back...

Of course as it's arcing it makes weird things on the screen, as you can see. The frequency of the igh show on the screen, is 100% correlated with the noise/pitch of of the CRT neck.

I was so excited to fix it and have it all working nice and all... and it's dead 

Can one find a CRT for this scope these days ? Or one that would fit and be electrically compatible at least ? How expensive are they, if at all available ?
I rescued the scope because it's cute and was free.... I can't justify nor afford to put lots of money for a new CRT... that would need to get shipped of course so might be damaged as well when getting to me 

It's 00H36, I am about to go to bed... and I am very sad, I won't be making sweet dreams..... 

EDIT : the parts list in the manual says the CRT is " P31 PHOSPHOR INTERNAL GRATICULE " , part number 5083-0353

EDIT #2 : just google the P/N. It found one on Ebay USA, sold for .... 570 dollars ! for 450kHz CRT !!! 
Scope is a write off 

https://www.ebay.com/itm/274969806314

Vince, do I see the sweep going vertically on the CRT?  If so, I'd first start by making sure the deflection plates are connected correctly.

-Pat

Edit to add - I'd think if something in the e-gun was physically damaged, you wouldn't be getting that relatively clean looking beam.  Doesn't mean it's not arcing internally, but I can't imagine that there's too much physical damage.  This might bear further exploration after you've gotten some sleep.

[med6753]

Vince, do I see the sweep going vertically on the CRT?  If so, I'd first start by making sure the deflection plates are connected correctly.

-Pat

Both the vertical and horizontal deflection plates are connected to the base of the CRT via those 2 transmission lines. I doubt they are mis-plugged.

Definitely sounds like internal arcing. 

[TERRA Operative]

Got my latest junker TDS754C scope last night, and junker it was....
Looks like it was pulled from a dumpster, the bottom was caved i  to the point it had actually punched cracks through the acquisition board, a shame as it was a board fitted with the 2M memory option. Memory chips are intact though, so I might try hitting it with a heatgun to remove them to transfer to a board with the standard 1M memory.

BUT it has a good PSU, good processor board, lots of little bits and pieces, aaannndddd a good colour CRT! (I need it for the TDS714L I'm fixing) and a PCMCIA HDD option! Yay!
Here's hoping the scope died before they did a secure erase, maybe some interesting stuff (software) on the HDD... gotta get the laptop running with linux or Win7, Win98 bluescreens when I plug the PCMCIA HDD into the port...

For now I have a bunch of good spare parts, good score for the 7000 yen grand total I paid.

[Cubdriver]

Vince, do I see the sweep going vertically on the CRT?  If so, I'd first start by making sure the deflection plates are connected correctly.

-Pat

Both the vertical and horizontal deflection plates are connected to the base of the CRT via those 2 transmission lines. I doubt they are mis-plugged.

Definitely sounds like internal arcing.

Yeah, good point.  I was thinking Tek with the neck pins and didn't look closely enough at the picture.     D'oh!

Probably toast. 

-Pat

[mnementh]

What do you have that's a more capable scope, and why do you think it is?

mnem
*toddles off to make some too-long bolts shorter*

Nothing as of yet, hence why I did contemplate buying it, that plus the Megazoom thing that I was curious to experience as you were raving about it. But, as I have said, using this scope is not the way I plan on acquiring the logic decoding capabilities. I would not mind having serial decoding and stuff on a scope, but not on this particular scope. I would be interested in having them in a fancy expensive modern scope like the R&S our German friend just acquired, for example, but even then, it still would not be in, replacement of a proper standalone logic analyzer. It would only be as a complement.

Any more questions ? 

Mmmmokayyy... here's the thing. These were the scopes that in their day, were some of the best you could get at doing one very important thing: observing a analog signal and the digital datastream associated with it at the same time, and triggering on either. This is a very common troubleshooting scenario you'll find yourself in when working with anything digital.

This single functionality is not something a standalone LA does as well, and as you've said, you don't have any more capable scope ATM. So for 50 bux, even if you have to skip lunches for a day or three, you could have had one of these groundbreaking scopes, and not an early one, but one of the mature, evolved designs... at a time when it would literally be one of the most, if not the most capable all-around scope on your bench. There's no way you could lose money on this thing.

I'll admit I've overlooked a great deal that was right next to something I had a raging nerd-boner for and didn't realize it until it was too late. More than once.  Every last one of us has done it, and nobody in here would think less of you for it; we'd all offer you our condolences and wish you better luck next time. 

From here, it looks like that's exactly what happened, and all the grumbling about appearances and such is just "sour grapes" type excuses to yourself for overlooking it; I remember you vehemently swearing on several occasions that you care about functionality first and appearance second. Well I can tell you this is a very functional scope, a real all-around workhorse, and you really did miss out.

If it'd been me (and honestly, I can see me possibly not even realizing what that scope was until I saw it in the pictures afterwards), I'd be calling myself aout loud repeatedly, in here, for at least a week. 


mnem
Just Like I did when I passed on that OWON from Arrow...