Test Equipment Anonymous (TEA) group therapy thread

[nfmax]

Ok just reflowed the bridge rectifier and it still does it after 2 minutes. I think the bridge was fecked by the rancid old caps that were on it before. I will order another one. Annoyingly I don’t have a suitable one in stock for once!

I have seen this exact same problem before with 'block' bridge rectifiers. It seems to be worse in the type where the leads are parallel to the axis of the mounting hole.

[bd139]

Today is good example of why us locals can't wait for the tourists and leaf peepers to go home. This is Minnewaska State Park and that picture is exactly how the trees look now. The park is absolutely over run today. Police have been up there all day ticketing illegal parking and in some cases towing cars. Earlier there was a 3 car accident on that Route 44 which shut it down completely for over an hour which made traffic at total clusterfuck. The map is deceiving. That road going up there is about a 5% grade and yes, that is a hair pin or "switchback" turn at 5 MPH which for some reason some driver's have trouble making and either go over the side or crash into a rock wall.

Ah yeah we get that here. I don’t go out walking and stuff until it’s fucking miserable weather and cold because they’ve all gone then 

[factory]

Drool. But I'm good. 

There is a HP 5248M with higher spec 105 series crystal oscillator on ePay in Europe, the title is missing the 8 from the model number.
Anyone interested should probably ask the seller to feed a signal into it, to prove whether the oscillator & tunnel diodes are working or not. 

eBay auction: #184477518267

I would have been interested if I didn't already have the crusty one that I need to finish repairing.

David

[bd139]

Ok just reflowed the bridge rectifier and it still does it after 2 minutes. I think the bridge was fecked by the rancid old caps that were on it before. I will order another one. Annoyingly I don’t have a suitable one in stock for once!

I have seen this exact same problem before with 'block' bridge rectifiers. It seems to be worse in the type where the leads are parallel to the axis of the mounting hole.

Interesting. These are the little round ones.

[nixiefreqq]

Ok found a unicorn on ebay. It's a very complicated and broken unicorn with three legs and half a horn but I'll fix that on arrival if no one else finds the auction or is less cheap than me. 

Very complicated, broken & a unicorn in the UK, wouldn't be something like a HP 5360A computing counter would it?

David

You mean this thing here?

Yes, that's the one, I don't have one yet & haven't seen one in the UK for many many years, someone on here has already warned me they are very very unreliable.

David

Edit: here is the last one I saw for sale in the UK;

am almost certain that my fortress of solitude contains more nixie counters than anyone else on this thread (with one possible exception).

BUT if anyone tries to give you one of those horrid THINGS turn and run.  run fast.  run far.

a counter that sits and mocks you......and never counts anything......is not a counter.



Go, and never darken my towels again!

[tautech]

Ok just reflowed the bridge rectifier and it still does it after 2 minutes. I think the bridge was fecked by the rancid old caps that were on it before. I will order another one. Annoyingly I don’t have a suitable one in stock for once!

I have seen this exact same problem before with 'block' bridge rectifiers. It seems to be worse in the type where the leads are parallel to the axis of the mounting hole.

Interesting. These are the little round ones.

Ahh, like the one Dave had to replace in his HP1740 video.
That one died without good reason too.

[Cerebus]

Yeah, that I can totally get... there is very little marketing involved in the production of the sensor heads or the thermistor mount; they're not very exciting. The meter itself is where marketing comes in, so every once in a while a more modern-looking model has to happen.

Where I got on the wrong side of this conversation was the prehistoric analog meter still being kept in stock at HPAK; that's what I was originally talking about, not the thermistor/mount as a separate entity (even tho, as I understand it, the mount and thermistor can actually be used by themselves).

I still suspect the old meter lingers there because TPTB know there is/are some large money customer(s) (be it military, manufacturing, scientific or calibration labs) that still have some need for that particular model. And I still suspect that reason is some standards document (maybe internal, maybe external) that is ultimately referred to again and again in which that meter is a requisite. Or maybe they keep it around because it is used to calibrate/validate subsequent models, and they have enough NOS to be able to offer some for sale to calibration labs etc, I dunno. 

But it makes no sense for them to spend the money keeping track of the damn things for 5+ decades if someone who makes these decisions didn't expect to recoup it from somewhere; I mean, FFS, the things outlived that crazy bitch and the HP television years...

mnem
 

But it makes no sense for them to spend the money keeping track of the damn things for 5+ decades if someone who makes these decisions didn't expect to recoup it from somewhere; I mean, FFS, the things outlived that crazy bitch and the HP television years...

mnem
 

Why would they bother to keep manufacturing it (the sensor)? Well, why not if it is good enough and there's a demand? It's surely more expensive to cut a new design and qualify that than to "keep track" as you put it, of an old design. This is all custom manufacture, there's no parts obsolescence to deal with.

The metering bit has been replaced (in 2011), 432A obsoleted and the N432A substituted for it.

RF power measurements aren't particularly high precision or high accuracy by their nature, that they're typically measured and specified on a dB scale gives a clue to that - so an analogue meter is probably always going to be 'good enough'.  There's no driving need for a new shiny more accurate or more precise meter - except perhaps the perception by some that a 'digital' meter is somehow more accurate than an 'analogue' one. The need to make automated measurements that one obviously can't with an analogue device would be a sane requirement, and that seems to have now been taken care of with the retirement of the 432A and the introduction of the new shiny digital N432A. The accuracy of the new shiny digital version is 0.1% ±5uW, which makes the 6¹/₂ digit ADC on it ever so slightly overkill. I suspect that the fact that it looks like one of the TrueVolt DVM range is no accident, but without schematics I can't prove my suspicion that it's a 34461 DVM with the input circuitry ripped out and replaced with interfacing to the power sensor.

As to the core measurement technology - a thermistor oven and a balancing bridge. That's probably going to be good enough for its purposes forever. The thermistor bit is easily characterised against primary standards. The bridge as a measurement technique is good enough that it's still being used as the core of measurement of some primary standards to stupid levels of precision.

Dude... come on. I stated very clearly in that very post that I was talking about the prehistoric analog meter. Obviously on some level you recognized that; or you wouldn't have omitted that part of the post. Hence, this entire point is well... pointless. 

And if you weren't sure, it should be obvious that I understand PRECISELY the point you are making here, because I stated the same thing in this post which precedes the one above:

So even HP hasn't come up with anything better in the 60+ years since it was released? What device is specified as the standard by which this device is validated? Bet it's another one of the same, isn't it...?

Also; are we talking about the meter here, or the mount and thermistor? The mount/thermistor I can see; there's no need for that to change, for the same reason the 84xx series sensors remain relevant. The meter itself...? come on; they have to have come up with something better by now.

mnem
 

mnem
 

Sorry, I didn't realise that you were looking for an argument not a discussion.

Obviously on some level you recognized that; or you wouldn't have omitted that part of the post. Hence, this entire point is well... pointless. 

When you start that sort of accusation, yeah, it's pretty clear that you just want another "Mnem's right" argument. On that point you know what you can do...

You know, I'm kindof sick of this accusation from you C. Let me set you straight... most of the time when you make this accusation, I'm not saying I'm right. I'm saying that if I'm wrong, that's okay. I have a right to be wrong, and I don't need you to fucking correct me. 

The internet is full of wrong people. Some of us are your friends. We don't need to be corrected every time we're wrong. We need to be corrected for imagined errors even less so.

When you so very obviously misquote me to have something to argue against... THAT I have a right to get a bit peeved over, and I'm gonna tell you about it. Suck it up and deal.

All it would have taken from you is a slightly less confrontational approach here... You could have taken any of the above posts where I said the same thing you said, but instead started with something like "Yes, I'm going to elaborate here for those playing along at home..." and we wouldn't be having this conversation.

But no... again, you had to take me to task in a public thread, over something I didn't even say. So now I'm telling you about it.

Maybe next time, try a PM before you smack my paws with a ruler in front of the whole class. 

mnem
 

I had quite a considered and carefully worded reply to this but you know what? Not worth the candle. People know what you're like, and I don't have to explain myself; people can read what we've both written and decide for themselves what the various intents were. The only point I will make is that I manage to keep up discussions on here, even with people I actively dislike, without peppering my replies with "FFS", "WTF" and facepalms directed at them.

[mnementh]

Sure C... whatever you say. But it just seems that's the only way we interact here anymore: You correcting me for some error, whether real or imagined.

Didn't used to be that way.

mnem
*sigh*

[bd139]

Ok just reflowed the bridge rectifier and it still does it after 2 minutes. I think the bridge was fecked by the rancid old caps that were on it before. I will order another one. Annoyingly I don’t have a suitable one in stock for once!

I have seen this exact same problem before with 'block' bridge rectifiers. It seems to be worse in the type where the leads are parallel to the axis of the mounting hole.

Interesting. These are the little round ones.

Ahh, like the one Dave had to replace in his HP1740 video.
That one died without good reason too.

Yeah that’s the ones.

I had to replace some in my 1740 I had as well 

[mnementh]

Got a old PC power supply? Most of the 4-6A bridges in my parts bin were salvaged from old ATX PSUs. Or is it form factor that's an issue?

mnem
 

[factory]

Ok found a unicorn on ebay. It's a very complicated and broken unicorn with three legs and half a horn but I'll fix that on arrival if no one else finds the auction or is less cheap than me. 

Very complicated, broken & a unicorn in the UK, wouldn't be something like a HP 5360A computing counter would it?

David

You mean this thing here?

Yes, that's the one, I don't have one yet & haven't seen one in the UK for many many years, someone on here has already warned me they are very very unreliable.

David

Edit: here is the last one I saw for sale in the UK;

am almost certain that my fortress of solitude contains more nixie counters than anyone else on this thread (with one possible exception).

BUT if anyone tries to give you one of those horrid THINGS turn and run.  run fast.  run far.

a counter that sits and mocks you......and never counts anything......is not a counter.



Go, and never darken my towels again!

That will be why the one in that recreated image is showing a count with no input, also in the two linked pages neither were shown powered up.
That one in the UK with the 5375A keyboard went for £20 as it was collection only, the only other in the UK is this one that made £155;


David

[Mr. Scram]

Yeah, that I can totally get... there is very little marketing involved in the production of the sensor heads or the thermistor mount; they're not very exciting. The meter itself is where marketing comes in, so every once in a while a more modern-looking model has to happen.

Where I got on the wrong side of this conversation was the prehistoric analog meter still being kept in stock at HPAK; that's what I was originally talking about, not the thermistor/mount as a separate entity (even tho, as I understand it, the mount and thermistor can actually be used by themselves).

I still suspect the old meter lingers there because TPTB know there is/are some large money customer(s) (be it military, manufacturing, scientific or calibration labs) that still have some need for that particular model. And I still suspect that reason is some standards document (maybe internal, maybe external) that is ultimately referred to again and again in which that meter is a requisite. Or maybe they keep it around because it is used to calibrate/validate subsequent models, and they have enough NOS to be able to offer some for sale to calibration labs etc, I dunno. 

But it makes no sense for them to spend the money keeping track of the damn things for 5+ decades if someone who makes these decisions didn't expect to recoup it from somewhere; I mean, FFS, the things outlived that crazy bitch and the HP television years...

mnem
 

But it makes no sense for them to spend the money keeping track of the damn things for 5+ decades if someone who makes these decisions didn't expect to recoup it from somewhere; I mean, FFS, the things outlived that crazy bitch and the HP television years...

mnem
 

Why would they bother to keep manufacturing it (the sensor)? Well, why not if it is good enough and there's a demand? It's surely more expensive to cut a new design and qualify that than to "keep track" as you put it, of an old design. This is all custom manufacture, there's no parts obsolescence to deal with.

The metering bit has been replaced (in 2011), 432A obsoleted and the N432A substituted for it.

RF power measurements aren't particularly high precision or high accuracy by their nature, that they're typically measured and specified on a dB scale gives a clue to that - so an analogue meter is probably always going to be 'good enough'.  There's no driving need for a new shiny more accurate or more precise meter - except perhaps the perception by some that a 'digital' meter is somehow more accurate than an 'analogue' one. The need to make automated measurements that one obviously can't with an analogue device would be a sane requirement, and that seems to have now been taken care of with the retirement of the 432A and the introduction of the new shiny digital N432A. The accuracy of the new shiny digital version is 0.1% ±5uW, which makes the 6¹/₂ digit ADC on it ever so slightly overkill. I suspect that the fact that it looks like one of the TrueVolt DVM range is no accident, but without schematics I can't prove my suspicion that it's a 34461 DVM with the input circuitry ripped out and replaced with interfacing to the power sensor.

As to the core measurement technology - a thermistor oven and a balancing bridge. That's probably going to be good enough for its purposes forever. The thermistor bit is easily characterised against primary standards. The bridge as a measurement technique is good enough that it's still being used as the core of measurement of some primary standards to stupid levels of precision.

Dude... come on. I stated very clearly in that very post that I was talking about the prehistoric analog meter. Obviously on some level you recognized that; or you wouldn't have omitted that part of the post. Hence, this entire point is well... pointless. 

And if you weren't sure, it should be obvious that I understand PRECISELY the point you are making here, because I stated the same thing in this post which precedes the one above:

So even HP hasn't come up with anything better in the 60+ years since it was released? What device is specified as the standard by which this device is validated? Bet it's another one of the same, isn't it...?

Also; are we talking about the meter here, or the mount and thermistor? The mount/thermistor I can see; there's no need for that to change, for the same reason the 84xx series sensors remain relevant. The meter itself...? come on; they have to have come up with something better by now.

mnem
 

mnem
 

Sorry, I didn't realise that you were looking for an argument not a discussion.

Obviously on some level you recognized that; or you wouldn't have omitted that part of the post. Hence, this entire point is well... pointless. 

When you start that sort of accusation, yeah, it's pretty clear that you just want another "Mnem's right" argument. On that point you know what you can do...

You know, I'm kindof sick of this accusation from you C. Let me set you straight... most of the time when you make this accusation, I'm not saying I'm right. I'm saying that if I'm wrong, that's okay. I have a right to be wrong, and I don't need you to fucking correct me. 

The internet is full of wrong people. Some of us are your friends. We don't need to be corrected every time we're wrong. We need to be corrected for imagined errors even less so.

When you so very obviously misquote me to have something to argue against... THAT I have a right to get a bit peeved over, and I'm gonna tell you about it. Suck it up and deal.

All it would have taken from you is a slightly less confrontational approach here... You could have taken any of the above posts where I said the same thing you said, but instead started with something like "Yes, I'm going to elaborate here for those playing along at home..." and we wouldn't be having this conversation.

But no... again, you had to take me to task in a public thread, over something I didn't even say. So now I'm telling you about it.

Maybe next time, try a PM before you smack my paws with a ruler in front of the whole class. 

mnem
 

I had quite a considered and carefully worded reply to this but you know what? Not worth the candle. People know what you're like, and I don't have to explain myself; people can read what we've both written and decide for themselves what the various intents were. The only point I will make is that I manage to keep up discussions on here, even with people I actively dislike, without peppering my replies with "FFS", "WTF" and facepalms directed at them.

Mnem having a hard time admitting he may have been wrong? Impossible! 

[med6753]

How far away from the park do you live, it sure looks really nice countryside 

About 20 minutes. On a weekday when the tourists are home. On a weekend? Forget it. 

And yes, the view out my window is almost as scenic.

More jackassery up there. A local property owner just called police to report there were approx 40 vehicles illegally parked on their property. Police responded that if they want the vehicles towed it's on them.

Some asshole ran out of gas and called 911. D'OH.   

[Cerebus]

Ah yeah we get that here. I don’t go out walking and stuff until it’s fucking miserable weather and cold because they’ve all gone then 

I got into the habit of doing all my hillwalking and proper climbing in September. The kids are back at school, so 90+% of the tourists have buggered off. The weather is either OK or still actually quite warm, you haven't gone into 'freezing your tits off' weather at low altitude, and, best bit of all if you're headed for Scotland, the bastard wee midges have buggered off or died.

Also, accommodation that is seasonal is still open, often only half occupied, if that, and consequently not asking top dollar. I managed to walk the West Highland Way in the 2nd week of September and every time we didn't feel like pitching the tent some hotel owner had a free room at a fair rate. (When we got to Kinlochleven we were planning to pitch a tent in a plot associated with a local hotel. When we went in to pay for the pitch, the hotel owner took one look at the soggy, bedraggled couple in front of him and said "Och, take a room on the house instead, ye look like ye need to dry out at bit".)

[med6753]

It appears we are going to need some. 




But perhaps this will divert the contentious discussion. 

[BU508A]

Fourty minutes ago, Shahriahr from TheSignalPath posted a new repair video.

[Cerebus]

You'll be disappointed. But then perhaps you've got other uses for a Med sized bag of popcorn, and if you do, please quietly draw a veil over it. We get enough unexpected 'education' from BD139's grasp of *ahem* alternative meanings of words and phrase like "my little pony" and "furry".

[Cerebus]

Fourty minutes ago, Shahriahr from TheSignalPath posted a new repair video.

I just spotted this in the 'while you were typing..' preview and, it being the kind of year it has been, I read as far as "Fourty minutes ago, Shahriahr from" and I'd already started thinking "Oh, God! Not another, please.".  Then I read on and: Phew!

[mnementh]

It appears we are going to need some.        But perhaps this will divert the contentious discussion.     

Nahhh... I'm done. "Contentious" for its own sake takes too much energy, and I've said all I have to say.

mnem
*weary sigh*

[bd139]

You'll be disappointed. But then perhaps you've got other uses for a Med sized bag of popcorn, and if you do, please quietly draw a veil over it. We get enough unexpected 'education' from BD139's grasp of *ahem* alternative meanings of words and phrase like "my little pony" and "furry".

On that subject, look on youtube for "swallowing marbles". Apparently it's a thing 

Ordered 10x W10 bridge rectifiers which are equivalent enough to the B380C1500 in the HM605 for the princely sum of £2.55 including delivery from ebay. I did look elsewhere but minimum quantities or delivery fees didn't cut it.

Some safer education as well from Curious Marc, probably my current favourite youtube channel

[Cerebus]

You'll be disappointed. But then perhaps you've got other uses for a Med sized bag of popcorn, and if you do, please quietly draw a veil over it. We get enough unexpected 'education' from BD139's grasp of *ahem* alternative meanings of words and phrase like "my little pony" and "furry".

On that subject, look on youtube for "swallowing marbles". Apparently it's a thing 

You see - suspiciously well informed. 

[BU508A]

Ordered 10x W10 bridge rectifiers which are equivalent enough to the B380C1500 in the HM605 for the princely sum of £2.55 including delivery from ebay. I did look elsewhere but minimum quantities or delivery fees didn't cut it.

I think, I'd have bodged something with four 1N5408. Have here a lot of them laying around.

[mnementh]

...Ordered 10x W10 bridge rectifiers which are equivalent enough to the B380C1500 in the HM605 for the princely sum of £2.55 including delivery from ebay. I did look elsewhere but minimum quantities or delivery fees didn't cut it.

Some safer education as well from Curious Marc, probably my current favourite youtube channel

Yeah... my original thought was to suggest cobbling a bridge out of 1N4007s, just to confirm the fault. Still think that's not a bad idea. 

Thanks for the vid... I'll look for more from him.

mnem
*poot*

[Cerebus]

On a totally different tack, yesterday I and the missus took a trek to the, recently opened, Home Bargains in Beckton in search of some cheap wiper blades as pointed out by Spec.

Failed in that respect, they didn't have any in that branch. What Spec didn't warn us, and this may just be the Beckton branch, is that Home Bargains is Chav Central. Well no, that's unfair, the clientele were the kind that Chavs get snobby about. I don't think that I've even been anywhere else before where I felt that we stuck out as being 'posh'. I almost feared us being singled out for punishment for our perceived poshness by the lumpy proletariat.  I'd swear that I saw three generations of the 'Fat Slags' from Viz all shopping together.

(People should have realised by now that 'posh' I ain't. I feel a swell of pride every time I pass a village common, that it's been named after me and my forebears.)

[Specmaster]

Ok just reflowed the bridge rectifier and it still does it after 2 minutes. I think the bridge was fecked by the rancid old caps that were on it before. I will order another one. Annoyingly I don’t have a suitable one in stock for once!

I have seen this exact same problem before with 'block' bridge rectifiers. It seems to be worse in the type where the leads are parallel to the axis of the mounting hole.

Interesting. These are the little round ones.

Ahh, like the one Dave had to replace in his HP1740 video.
That one died without good reason too.

Yeah that’s the ones.

I had to replace some in my 1740 I had as well 

Can't you fabricate a temporary one from 4 diodes, I think you may have sufficient in your parts bin to prove if this is the issue or not?