Test Equipment Anonymous (TEA) group therapy thread

[AVGresponding]

This bloody thing has been going off for about six or seven hours at the flats my brother lives at, both with a fire alarm (false) & general fault.  Shame it doesn't tell you which flat caused the problem.



David

Looks vaguely familiar, is it a Proteus maybe?

In any case, it's definitely an addressable system, so there's no good reason why it shouldn't be giving an exact location.

In fact, BS5839 parts 13.2.4 a and b state that this should be displayed, and that there should be a geographic zone map adjacent to the CIE (control and indication equipment - the fire alarm panel) and any mimic/repeater panel.

The only possible (legitimate) reason for the panel not displaying this, is if the panel has been interfaced to an older, non-addressable system, in which case you can only get zone information.

The fire and subsequent fault are likely some halfwit burning some toast, and then removing the detector from its base in an effort to hide their mistake.


Back to the TE... the seller has marked my Solartron 7065 as posted now, he wanted to repair it before he sent it, and also offered a £20 discount for the delay, bringing the shipped cost down to £42...

Annndd I bought another boat anchor, semi-accidentally (I was expecting to get overbid):


And also, a nice (I believe) LCR meter, which wasn't cheap, bit of a bidding war, £169 shipped   

These were around $2k new, if I'm not mistaken (hope I'm not).

And finally, saw this go for £90 + £11 shipping, seems expensive to me, or am I missing something?

[Martin.M]

Edit (not worth a new post)  Sold for $182.50.  Winning bid came in the very last second.

How many valves in it? What are they worth?

the audiophools question 

[Brumby]

How many valves in it? What are they worth?

Not a question of interest.

I'm past the point of trafficking in cannibalised parts - and it goes against the grain a bit.  Besides, it's not the sort of thing I would really like to wrangle.

Besides, it was just as well I stepped back... bloody eBay sent an SMS to SWMBO's phone as well as mine (must be some sort of IP address/handset tracking  ) and I was asked if was bidding on another oscilloscope - to which I was able to honestly say "No, I was only watching it".   

[bd139]

Thanks all for the 3DP tips. I looked at mine and it is indeed worn already. I will order an aluminium one on Monday 

Had this today which was a pain in the arse: https://www.eevblog.com/forum/chat/fireangel-smoke-alarm-stupid-engineering/msg2788564/

Good job the house didn't burn down!

[med6753]

Well, fix your damn toaster.  All the smoke/CO alarms here in the 4 apartments, plus the hallways and basement boiler room are linked together. So if one knucklehead burns the toast at 5 AM the entire complex knows about it. Luckily they are NOT linked to a dispatch panel or we would have had the fire dept on scene several times for no good reason.     

[mansaxel]

this is the warm RF probe, AC up to 30V
Telefunken E91AA = 6AL5W, EAA91 do the job also.

Now that’s rather sexy. Good for winter radio work 

I get a little pleasant surprise from the heat every time I reach for my Marconi VTVM probe. Can vouch for said goodness.

[worsthorse]

Well I didn't bid on this...

eBay auction: #283562586328

But I did put in a snipe on this, not expecting to win:

eBay auction: #202819208174

And then I won.     So now I have a voltage calibration source.



Between this and the stack of Tektronix gear, I guess I am more or less building a state-of-the art 70s calibration lab. 

[URI]

Yeah, well, while working on my bench/TE rack I sniped on a HP 6827A and won.   

The HP 6827A is a bipolar power supply or amplifier.
In the range from DC to 15kHz/30kHz it'll be a versatile power amplifier for my function generator powering test circuits or parts e.g. relays. 


[linked in from ebay]

It's very good optical shape and is located in central Europe so no hassle with Bitney Powes.. 

[URI]

BTW, it's quiet a struggle to keep up with the thread..      

[tggzzz]

Well I didn't bid on this...

eBay auction: #283562586328

But I did put in a snipe on this, not expecting to win:

eBay auction: #202819208174

And then I won.     So now I have a voltage calibration source.

(Attachment Link)

Between this and the stack of Tektronix gear, I guess I am more or less building a state-of-the art 70s calibration lab. 

So now you need a 70s DVM to measure the voltage source.

There are 11 Solarton 7075s for sale next week, but none of them have a lead.  My spare one does

[nixiefreqq]

well it had to happen sooner or later.  needed TE to fix a problem.

my national sw-54 receiver suffers from a well know design fault.  the dial lamp is powered from a 6.3v tap on the 35z5 rectifier.  problem is that the plate current for all the tubes also goes thru the poor little #47 lamp.  no shit....see this link  https://www.philcorepairbench.com/blown-pilot-lamps-and-35z5-open-filament/ .

all is well unless you switch it on an off again too quickly (or if the power company decides to balance their load and switches our development from our north substation to the one south of us).  when that happens the full current necessary to recharge the filter caps zaps the lamp.

have been thru half a dozen #47's in the past two months.  tried a pair of back to back 6.8v, 1 watt zener's across the lamp to clamp the voltage (based on a recommendation from an antique radio repair website).  it sorta' worked but eventually the diodes would fail short. 

decided to try the trick from one of daves videos and make a voltage clamp using the B-E junctions from a pair of transistors.  had a bag of 65 fairly beefy transistors that have a BE reverse breakdown that measured at 10.2V.  but first needed to see what the voltage across the lamp looked like in normal operation.   didn't want to screw up and blow up a real scope, but no worries.  the fluke is a scopeMETER.  so it is happy doing floating measurements as long as you are not more than 300v above ground ( i think that is what the manual said).

you can see that the voltage drop just from the filament tap  peaks at about 4.6v, while the peak with the plate current thrown in hits 9.4v.  so a 10.2v clamp should not affect normal operation, but should kick in and stop a quick on/off from killing the lamp.

and damn if it does not work just great.  radio sounds the same as before and multiple attempts to kill the lamp or the transistors did neither. 

winner winner chicken dinner.

ps  if anyone wants to know what those transistor are.....dunno.  have a bag of about 60 of them.  they are definitely silicon npn.  the part number stamped on them crosses over to nsn 5961-00-230-8853.   cage code 98230 comes up as......ummmmmmm......No Such Agency.  wonder what the hell they came out of?  am watching right now for black helicopters. 


 

[factory]

This bloody thing has been going off for about six or seven hours at the flats my brother lives at, both with a fire alarm (false) & general fault.  Shame it doesn't tell you which flat caused the problem.



David

Looks vaguely familiar, is it a Proteus maybe?

In any case, it's definitely an addressable system, so there's no good reason why it shouldn't be giving an exact location.

In fact, BS5839 parts 13.2.4 a and b state that this should be displayed, and that there should be a geographic zone map adjacent to the CIE (control and indication equipment - the fire alarm panel) and any mimic/repeater panel.

The only possible (legitimate) reason for the panel not displaying this, is if the panel has been interfaced to an older, non-addressable system, in which case you can only get zone information.

The fire and subsequent fault are likely some halfwit burning some toast, and then removing the detector from its base in an effort to hide their mistake.

I didn't note the brand, are Proteus units good or crappy generic re-brands? My brother doesn't have a key to the lobby as he lives on the ground floor, so the rather crap phone picture was taken through the window with zoom, he said someone may have removed a detector/sounder unit as they kept setting it off smoking the last time it went off, each block has a panel covering six flats, all linked together.

Highly likely it's part of an older system as they didn't bother removing old detector/sounder units last time they replaced them, the new sounders are much louder then the crap they installed where I work (which now can't be heard over the noise of some machines  ).

Back to the TE... the seller has marked my Solartron 7065 as posted now, he wanted to repair it before he sent it, and also offered a £20 discount for the delay, bringing the shipped cost down to £42...

Annndd I bought another boat anchor, semi-accidentally (I was expecting to get overbid):


And also, a nice (I believe) LCR meter, which wasn't cheap, bit of a bidding war, £169 shipped   

These were around $2k new, if I'm not mistaken (hope I'm not).

And finally, saw this go for £90 + £11 shipping, seems expensive to me, or am I missing something?

The Iso-Tech stuff is branded for RS only, there doesn't seem to be many decent bench LCR meters on the second hand market which keeps prices high.

They had lots of that modular Hameg stuff at the college I went to, I imagine it has all been replaced by now, the building certainly has.

David

[factory]

Well I didn't bid on this...

eBay auction: #283562586328

But I did put in a snipe on this, not expecting to win:

eBay auction: #202819208174

And then I won.     So now I have a voltage calibration source.

(Attachment Link)

Between this and the stack of Tektronix gear, I guess I am more or less building a state-of-the art 70s calibration lab. 

So now you need a 70s DVM to measure the voltage source.

There are 11 Solartron 7075s for sale next week, but none of them have a lead.  My spare one does

I assume the shipping to the US would be more than the value of a 7075 too, plus how much would need altering for 60Hz use?

David

[Martin72]

BTW, it's quiet a struggle to keep up with the thread..      

Absolute...

[Specmaster]

Well I didn't bid on this...

eBay auction: #283562586328

But I did put in a snipe on this, not expecting to win:

eBay auction: #202819208174

And then I won.     So now I have a voltage calibration source.

(Attachment Link)

Between this and the stack of Tektronix gear, I guess I am more or less building a state-of-the art 70s calibration lab. 

That is as about spot on as you'll get with as well, good going, was it cheap or what? 

[factory]

There you go, fixed it for @med.



David

Your ticket to hell just got upgraded to Business class.

Even I agree that doesn't look right.  Should remain all black.

At least the front panel was left alone.


That's not an invitation, either!

Thanks for the hell ticket upgrade, it's got to be better than Crewe. 
And changing the front panel would be beyond my editing skills, I don't remember @med painting any front panels either.
For the price you should be able to choose the colour, I would prefer it with a neon display, grey front panel & the 60's blue (or the 50's brown) they used for the covers/case, plus this logo. 



David

P.S. I don't need need anything 8.5 digit here anyway, that rabbit-hole is not for me.

[URI]

A blue HP voltmeter? Why not?   
The front plate shouldn't be left alone black..   



The colour looks quiet good.
I like it.     

[factory]

Almost forgot about this blue HP oscillator.

eBay auction: #282885696237



David

[tggzzz]

So now you need a 70s DVM to measure the voltage source.

There are 11 Solartron 7075s for sale next week, but none of them have a lead.  My spare one does

I assume the shipping to the US would be more than the value of a 7075 too, plus how much would need altering for 60Hz use?

The mains voltage is "100-264V (no mains tap)".
The 50Hz/60Hz is set with a link between test points.

Mine comes in a wooden case made by the previous owner, the RAF.
I've had to "condense" three faulty 7075s into two working ones. I buggered one board with the slip of a scope probe. The RAF buggered the other's switches with a stupidly placed wooden support; I'll have to move that!
Mine comes with a lead. I took the lead and front panel socket from my buggered 7075. The lead and socket are (extortionately expensive) Fischer connectors, but have a different pinout for some reason.

I've just noticed the input impedance is only 1Mohm//150pF.
Bear in mind that calibration is done by many trimpots; you may regard that as an advantage or disadvantage I've tweaked it as best as I can.

You might, or might not, be able to get an idea of the shipping cost from another 7075 for sale: https://www.ebay.co.uk/itm/Schlumberger-Solartron-7075-Digital-Voltmeter-3/223747731227 That price is silly; I have no idea what offers they might accept.

[Neomys Sapiens]

And finally, saw this go for £90 + £11 shipping, seems expensive to me, or am I missing something?
[/color][/b]

Even in Germany, where the Hameg products are most numerous, I have not seen a base unit with two modules for under 100€. To the contrary, even empty base modules can be over 100.-.

[URI]

I fetched up two capacitor decades on ebay -from UK:



Does anyone know the companies shown on the plates?:



Different sellers, different auctions.
One for £24,99 and the other one for £19,99.
Nobody seemed to be interested in those. They both were a buy now offer that had already run several days.

I tested them with my HP 4362A LCR meter and they both are within their 1% spec!   
The larger one with the 50pf to 160pf vernier was offered 'for parts or not working' and it was indeed.
But nothing serious: One capacitor connector was broken what could be fixed with a little soldering job.   

[factory]

They look like the same company to me, maybe changed name at some point as the address hasn't changed, there was one of those J.J. Lloyd decade capacitor or resistor boxes (can't remember which) at work.

David

[factory]

So now you need a 70s DVM to measure the voltage source.

There are 11 Solartron 7075s for sale next week, but none of them have a lead.  My spare one does

I assume the shipping to the US would be more than the value of a 7075 too, plus how much would need altering for 60Hz use?

The mains voltage is "100-264V (no mains tap)".
The 50Hz/60Hz is set with a link between test points.

Mine comes in a wooden case made by the previous owner, the RAF.
I've had to "condense" three faulty 7075s into two working ones. I buggered one board with the slip of a scope probe. The RAF buggered the other's switches with a stupidly placed wooden support; I'll have to move that!
Mine comes with a lead. I took the lead and front panel socket from my buggered 7075. The lead and socket are (extortionately expensive) Fischer connectors, but have a different pinout for some reason.

I've just noticed the input impedance is only 1Mohm//150pF.
Bear in mind that calibration is done by many trimpots; you may regard that as an advantage or disadvantage I've tweaked it as best as I can.

You might, or might not, be able to get an idea of the shipping cost from another 7075 for sale: https://www.ebay.co.uk/itm/Schlumberger-Solartron-7075-Digital-Voltmeter-3/223747731227 That price is silly; I have no idea what offers they might accept.

There is a 7075 in my repair queue, with a simple looking fault of only displaying even numbers, it came with no feet as usual (or handles), I do have a matching lead for it.

I agree that price is silly, they haven't bothered to show if all the displays are working either, plus no input lead or shoes.

David

[bitseeker]

BTW, it's quiet a struggle to keep up with the thread..      

Yup. I've been struggling quite a bit with that lately. However, it's always great to see the activity.

[Mr. Scram]

You guys realise you don't have to read everything right?