Test Equipment Anonymous (TEA) group therapy thread

[Cubdriver]

So now need to figure out the 6C4 and I am good.... am just one single tube away from resurrecting this poor HP scope !

1/2 a 12UA7:
http://www.r-type.org/exhib/aaa0038.htm

Sensibly equivalent to:
CV133 CV852 EC90 L77 V741

Just don't try to make one by sawing a 12AU7 in half - they don't like that.

In general with tubes, a later suffix can safely replace an earlier suffix (eg a 6SN7GT can be replaced by a 6SN7GTA or GTB, and the GTA can be replaced by the GTB)  Incidentally, for octal based tubes, a plain number (6L6, for instance) is a metal tube.  The 6L6G is a glass tube with a shouldered envelope, and the 6L6GT has a tubular glass envelope (what we mostly consider a 'normal' tube).

Shouldered envelopes are shown below in the AK radio chassis photo:


The A and B suffixes indicated either an improved version of the tube, or a tube with a heater with controlled warm up characteristics (these became more common late in the game as series-string filament designs became more common as manufacturers stopped using transformers in an effort to cut costs).

-Pat

[Vince]

Please see my response [..]

I DID see your response... but BEFORE you edited it to add some stuff, so I had no way to know you edited it with new info ! 

So about 200 Euros to retube the thing, kinda how I ballparked it in my head... so not surprised.


But as I said in my last message, I have everything I need in my old Teks, bar one 6C4 and I just found an ad for  Sylvania NOS one in France ( = cheap shipping...), just messaged the guy to see how much he wants for it exactly. There are other sellers in France for it, not NOS, but who cares, as long as it works.. it's not like the tubes I will pull from my old Teks were NOS either ! 
Just want to get this HP scope back and running, not spend lots of money to fill it with NOS tubes everywhere... just doesn't make sense financially nor technically, being such low end scope, and just can't afford it in any way shape or form, anyway.  That 6C4 would be the only NOS tube in the scope...

A good source for tubes is this website: http://www.die-wuestens.de/

Thanks for the link ! 

[Vince]

In general with tubes, a later suffix can safely replace an earlier suffix (eg a 6SN7GT can be replaced by a 6SN7GTA or GTB, and the GTA can be replaced by the GTB)  Incidentally, for octal based tubes, a plain number (6L6, for instance) is a metal tube.  The 6L6G is a glass tube with a shouldered envelope, and the 6L6GT has a tubular glass envelope (what we mostly consider a 'normal' tube).

[..]

The A and B suffixes indicated either an improved version of the tube, or a tube with a heater with controlled warm up characteristics (these became more common late in the game as series-string filament designs became more common as manufacturers stopped using transformers in an effort to cut costs).

Interesting.. thanks for the info Cub ! 

[mindcrime]

Huh. Was that a **thump** outside my door, and more muttered cursing from the Fedex guy?



Why yes, yes it was!



I have a feeling this is about to see extensive action.



The anticipation mounts...



Just gotta get past this layer of bubble wrap and packing tape.



Wait, what's this? A box inside a box?? Very sneaky...



Another layer of packing material?!?? Gotta give it to this seller, they didn't want this damaged in transit.



And there she is, in all her majestic glory!



Yes, it's a 53310, as promised.



Rear panel.



As far as I know this particular unit has none of these options. Oh well.



Looks important...

[kj7e]

You need a good GPSDO to reference the 53310A with now.

[cyclin_al]

OT: My current "China-Direct" madness: maybe getting back into Cheap RC cars. These from WLToys are pretty well-known to flex not break and are fully repairable with all parts available, altho 540 brushed and a bit cheap on the electronics. Some bashing fun with my son in the future, if they actually make it to me as promised.   

I've done business before with TomTop; they're another like GearBest & bang-em-good. Pray for me, this is aboot USD$130 less than 2 of these would normally cost based on shopping elsewhere; actually, right at release prices 3 years ago, before they made a name for themselves. Otherwise, will be a bit of PP dispute, etc.

https://www.tomtop.com/p-rm5683gr.html

mnem
 

No apologies here for being an enabler!!!  Or rather, my son is the enabler by asking us about this for an upcoming birthday, and then me being reminded by SWMBO ... it is easy to enable the enablers 

So do I understand this correctly that simply changing the currency from $CAD to $USD and having PayPal do the conversion saves $50CAD, rather than doing the transaction directly in $CAD ?

Also, comparing to bang-em-good, the estimate for duties, taxes & fees would be in the $120CAD range?

Call me grasshopper, but I think I have much to learn about international transactions....

[cyclin_al]

this is where my internal dictionary fails.

My English is somewhat usable (minus the errors introduced by google autocorrection/special vocabulary that I rarely use), but how should I know that you are not supposed to call something by its generic name ...

My intention was to inform, so you could build your internal dictionary.
The extra detail was to make it a bit more memorable. 

For me, if it is not memorable, it ends up on a mental (not so) sticky note, rather than in the internal dictionary.  SWMBO can confirm that 

[mindcrime]

You need a good GPSDO to reference the 53310A with now.

That I have. What I need, if anything, is a distribution amplifier so I can use it for all my test gear instead of having to unattach/reattach all the time.

[cyclin_al]

You need a good GPSDO to reference the 53310A with now.

That I have. What I need, if anything, is a distribution amplifier so I can use it for all my test gear instead of having to unattach/reattach all the time.

And now we know how long a "while" is 
 

[mnementh]

Huh. Was that a **thump** outside my door, and more muttered cursing from the Fedex guy?
(SNIP)
   Wait, what's this? A box inside a box?? Very sneaky...   

Another layer of packing material?!?? Gotta give it to this seller, they didn't want this damaged in transit...

   
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg2364543/#msg2364543

Pfffffft.... amateur. Box inside a box inside a box... AND a custom 3DP front cover made for the 454 I sent Bitseeker.

In all honesty, I was just grateful to the man for giving her a good home. She and I had... history.

mnem
MAXIM 37: "There is no 'overkill.' There is only 'open fire' and 'I need to reload'... this into yet another box."

[tautech]

You need a good GPSDO to reference the 53310A with now.

That I have. What I need, if anything, is a distribution amplifier so I can use it for all my test gear instead of having to unattach/reattach all the time.

And now we know how long a "while" is 
 

Same as the long weight we used to send the apprentice to the hardware store to get ! 

Which reminds me of another unfinished project mostly done except for the 11lb sash weights are too light for the new double hung window installed back in the summer. They need be ~2.5lb longer in weight so the bloody window doesn't work as a guillotine instead !

[mindcrime]

Blah, blah..  A distribution amplifier isn't "test equipment", it's just a mere accessory. That doesn't count! 

Besides, I haven't bought it yet anyway...

[mnementh]

OT: My current "China-Direct" madness: maybe getting back into Cheap RC cars. These from WLToys are pretty well-known to flex not break and are fully repairable with all parts available, altho 540 brushed and a bit cheap on the electronics. Some bashing fun with my son in the future, if they actually make it to me as promised.   

I've done business before with TomTop; they're another like GearBest & bang-em-good. Pray for me, this is aboot USD$130 less than 2 of these would normally cost based on shopping elsewhere; actually, right at release prices 3 years ago, before they made a name for themselves. Otherwise, will be a bit of PP dispute, etc.

https://www.tomtop.com/p-rm5683gr.html

mnem
 

No apologies here for being an enabler!!!  Or rather, my son is the enabler by asking us about this for an upcoming birthday, and then me being reminded by SWMBO ... it is easy to enable the enablers 

So do I understand this correctly that simply changing the currency from $CAD to $USD and having PayPal do the conversion saves $50CAD, rather than doing the transaction directly in $CAD ?

Also, comparing to bang-em-good, the estimate for duties, taxes & fees would be in the $120CAD range?

Call me grasshopper, but I think I have much to learn about international transactions....

Well, no. This is supposed to be the 12428, not the stripped-down 12427. My shopping elsewhere indicates the usual price for this is somewhere around $130-150 plus shipping. And Duty/tariffs (or with bang-em-good, some add-on in the form of ~$11 for "Duty Insurance", which they supposedly refund you up to 60% of purchase price if you get hit for duty, etc). My cheapest deal with Banggood was two 12427s for CAD$324 with that Duty & Shipping insurance deal. And if they hit me up for duty, I'd have to pay that and brokerage fees up front, then get it back from Banggood... 

Getting it for $99 each shipped TO CANADA and supposedly TomTop pays the Duty ahead... THAT where the total savings of USD$130 for two come in, based on my conservative estimate and PayPal's currency converter.



Supposedly. If the deal is on the up & up. We'll see what comes; it's been like... I dunno 5 years since I bought anything from TomTop...? I got what I ordered, and I made a working FPV facebox "goggles" for aboot $60 all in.

mnem
 

[beanflying]

Brain fried by a 15 minute EMP stream. Coffee failed to reboot it so will Beer work or is a replacement required

Noisy uncomfortable and Tinnitus aggravating things MRI's

[mnementh]

Could be a lot worse. 

mnem
*toddles off to ded while the toddling's good*

[KrudyZ]

I just walked into my lab to see my Tektronix 577 curve tracer catching fire.
I think I had left it on accidentally for a few days.
Luckily, it had decided to blow up while I was around, rather than being at work.
It smells bad, but at least the house is still standing...

[tonyalbus]

You need a good GPSDO to reference the 53310A with now.

That I have. What I need, if anything, is a distribution amplifier so I can use it for all my test gear instead of having to unattach/reattach all the time.

You can use these boxed.. trigger signal distributer amp DC-200MHz Square: https://s.click.aliexpress.com/e/_APe8EN
or these that only do 10 MHz Sine: https://s.click.aliexpress.com/e/_AgM105
and i have this one: FDIS-5 with also has 1 MHz Sine and 2 and 5 MHz out.. for older equipment...:  https://s.click.aliexpress.com/e/_A1iByH

you have the last 2 with and without TCXO .. i have 1 with.. as a backup for when the gpsdo fails.... but better to have 2 gpsdo's   

[beanflying]

Went looking for human Brain Booting fuel with a plan of Roast Chook for dinner. Walked out with a small Pork Roast not all of the crackling made it home for a sandwich for lunch. Brain is less fuddled or at least it is confused by taste receptors working overtime 

Lucky escape on the tracer too  I have a SOlartron/RIFA loaded cardboard box to unpack but that is a tomorrow job.

[Robert763]

[...]
But, maybe a ray of light : today as well, I notice this thing :

https://www.leboncoin.fr/bricolage/1984157768.htm?ac=206978287

An old tube HP scope, model 120B.. FOR FREE !!!
... the guy said he stole all the tubes from it, and is giving away the corpse...

      

[...]
I just downloaded the service manual for it.. it's got 19 tubes in it. I can't afford to buy that many tubes to bring it back to life, would cost me as much my car, and even if I could buy al those tubes, I could not justify such an extravagant expense for such a low spec scope anyway...

BUT....It's free, it's cute, in good nick, it's a cool piece of HP history.. only 10 Euros to pay to get it (for shipping).... I just want to buy it somehow !!!
My cheap/affordable entry to vintage HP test gear, you gotta start somewhere !!! 

Please tell me your thoughts... should I, or shouldn't I ?? 

Could you provide a list of all those tubes? Perhaps some people here can help you with that.

Edit:

Okay, I did a little research and found a list of the tubes from the 120B on radiomuseum.org.
It contains 17 tubes, including the CRT.

Here is my list (haven't found out yet, how this bloody table is working in SMF)

Code: [Select]

tube type         units     available at     price per unit
12AU7 / ECC82     5         reichelt.de      12 EUR
6DJ8 / ECC88      3         reichelt.de      18 EUR
6GH8A / ECF82     3         reichelt.de      7 EUR
6AU6 / EF94       1         reichelt.de      9 EUR
6AQ5 / EL90       1         reichelt.de      7 EUR
6C4 / EC90        1         reichelt.de      11 EUR
12B4A / ---       2         ebay.de      ca. 10 EUR

This will make overall costs for the tubes: 182 EUR exkl. shipping.
It might be doable. Perhaps, if you could find used tubes it may become much cheaper.

Good luck with that.

You have a CRT a mains transformer and all the hardware, time to desigin your own solid state 'scope. 
Well it s possible. Either FETs to replace the tubes or a bunche of op-amps givn the low frequency.

[capt bullshot]

Fun with TEA:

Testing the linearity / accuracy of that Kelvin Varley divider (Thanks to DC1MC) vs. the ratio transformer



One connects some AC voltage (30V @ 100Hz provided by the Fluke) to both inputs, and measures their output differential. Usually an AC Null Meter gets used here, since I don't have a proper one, I'm using the N4L PSM2200, which features an isolated input and a phase sensitive meter function.



Then adjust the ratio transformer to find the minimum, and see the KVD deviation from ideal setting. These things are quite good, tested all settings of the 0.1 and 0.01 dial each and found less than 10ppm difference.

[Robert763]

You need a good GPSDO to reference the 53310A with now.

That I have. What I need, if anything, is a distribution amplifier so I can use it for all my test gear instead of having to unattach/reattach all the time.

Look for an Extron Video distribution amplifier. Either composite/component or RGB (with BNCs) They work gread as 10MHz distribution amps. The VGA gives you 5 channels. They can be used for different frequencies or cascaded (gives extra isolation between equipment) Being 75R is not really an issue but you could change the termination and source resistors.
$30 BIN for this one https://www.ebay.com/itm/363386344111?

[Robert763]

You need a good GPSDO to reference the 53310A with now.

That I have. What I need, if anything, is a distribution amplifier so I can use it for all my test gear instead of having to unattach/reattach all the time.

You can use these boxed.. trigger signal distributer amp DC-200MHz Square: https://s.click.aliexpress.com/e/_APe8EN
or these that only do 10 MHz Sine: https://s.click.aliexpress.com/e/_AgM105
and i have this one: FDIS-5 with also has 1 MHz Sine and 2 and 5 MHz out.. for older equipment...:  https://s.click.aliexpress.com/e/_A1iByH

you have the last 2 with and without TCXO .. i have 1 with.. as a backup for when the gpsdo fails.... but better to have 2 gpsdo's   

See my other post, why buy chinese tat n a PCB ended box when you can get an Extron for half the price?

[mansaxel]

See my other post, why buy chinese tat n a PCB ended box when you can get an Extron for half the price?

I've got a S-video matrix (2off BNC per channel) from Extron -- that I got for free, because the seller shipped it in error when I shoulda gotten an audio matrix. I was refunded and not told to ship it back.

I've tried it as a 10MHz DA, after all, a matrix is just an expensive (not this time) DA with input selectors  . The input is 75Ω of course, but the real problem is that the inputs get overdriven (Meinberg GPSDO giving it a 5V sine input signal) to the degree that some consumers fail to lock on to the outputs. . A pad and impedance conversion is probably necessary. I've done some resistor shopping for this but ran out of round tuits en route.  Will try and see if I can reach some conclusion.

The other reason to get the FDIS-5 of course is the 1 and 5 MHz outputs, useful for boat-anchors. The 1PPS I do not think much of -- it can't possibly be anything else than a 1Hz random pulse train, not tied to UTC. (In my world, the 10MHz is for "frequency" and the 1PPS is for "phase", with an IRIG or NTP signal to cater for "when". A 1PPS not tied to UTC is mostly pointless.)

/Måns, I am not a time nut, only a broadcast network engineer, and those are closet time-nuts!

[Gromitt]

[submarines]

We have three museum subs in Sweden, our first, HMS Hajen and a quite late one, HMS Neptun at the main naval museum, and a WW2 one, HMS U3, at the city museum in Malmö, where subs have been built and still are. I've been to them all.

There's also HMS Nordkaparen at Maritiman in Gothenburg. http://www.maritiman.se/fartygsflottan/ubaten-nordkaparen

[beanflying]

So the Solartron has lived a life of travel it seems. Made in the UK, Calibrated in Washington State @ Fluke, Worked in South Australia for Defense Research, Moved to Western Australia followed by a 4000km move to me. Time for a life of luxury and semi retirement.

Wonder if it left Oz for work in the USA after DRCS or before and then came back