Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 18814367 times)

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Offline m k

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130075 on: August 17, 2022, 08:37:01 pm »
Other end is different.

Soldering required 2.0AH for Gesipa 14.4V battery tool battery pack 14.4 Volt
https://www.ebay.com/itm/233282666164
Advance-Aneng-Appa-AVO-Beckman-Danbridge-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-OR-X-REO-Simpson-Sinclair-Tektronix-Tokyo Rikosha-Topward-Triplett-Tritron-YFE
(plus lesser brands from the work shop of the world)
 

Offline Zenith

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130076 on: August 17, 2022, 08:39:36 pm »
idk wtf is going on, I bid 88.88, which was the winning bid, but somehow I'm not the winner? Fuck ebay, I'm done.

did someone else bid the same 88.88 but before you? Then the first bidder gets it. Had you set 88.89 it would be yours. Or sometimes you loose somtime the others win :o
Yes, sadly... bidding "clever amounts" like this can bite you in the arse. You're not the only one who likes to be clever.  ;)

If it's something you really want, then dig deep; until it hurts. That way when someone tops you by one copper, you can honestly say to yourself "It was too fucking much".

mnem
 :blah:

The correct amount to bid is that at which you will be equally unhappy whether you win or lose

An interesting thought, but how do you decide that in advance? There are such things as buyer remorse and failed buyer regret. "If only I'd bid an extra fiver, I could have had that and wouldn't have to keep looking".

Then ebay can be so strange. Years ago I was interested in an AWA low distortion audio oscillator, which rarely turns up. I asked the seller a question, which he answered, and he said he was selling three, one after the other. The first went for £75,  I got the second for £27, the third went for £85. There was something else I bid on, and also three were sold by the same ( a different) seller. The first went for £20, I paid £30, the last went for £25.


 

Offline m k

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130077 on: August 17, 2022, 08:40:17 pm »
@tautech will go for that specialized premix husqvarna certified mix that does cost a bit more but comes without all those pesky additives good for the road but bad for the woods ...

We have a Neste special smokeless gas, used to be >5€/l.

E,
4,39€/l today.
A must say those who use the machine for work.
« Last Edit: August 17, 2022, 08:47:07 pm by m k »
Advance-Aneng-Appa-AVO-Beckman-Danbridge-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-OR-X-REO-Simpson-Sinclair-Tektronix-Tokyo Rikosha-Topward-Triplett-Tritron-YFE
(plus lesser brands from the work shop of the world)
 

Online nfmax

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130078 on: August 17, 2022, 08:52:56 pm »
idk wtf is going on, I bid 88.88, which was the winning bid, but somehow I'm not the winner? Fuck ebay, I'm done.

did someone else bid the same 88.88 but before you? Then the first bidder gets it. Had you set 88.89 it would be yours. Or sometimes you loose somtime the others win :o
Yes, sadly... bidding "clever amounts" like this can bite you in the arse. You're not the only one who likes to be clever.  ;)

If it's something you really want, then dig deep; until it hurts. That way when someone tops you by one copper, you can honestly say to yourself "It was too fucking much".

mnem
 :blah:

The correct amount to bid is that at which you will be equally unhappy whether you win or lose

An interesting thought, but how do you decide that in advance? There are such things as buyer remorse and failed buyer regret. "If only I'd bid an extra fiver, I could have had that and wouldn't have to keep looking".

Then ebay can be so strange. Years ago I was interested in an AWA low distortion audio oscillator, which rarely turns up. I asked the seller a question, which he answered, and he said he was selling three, one after the other. The first went for £75,  I got the second for £27, the third went for £85. There was something else I bid on, and also three were sold by the same ( a different) seller. The first went for £20, I paid £30, the last went for £25.
The lesson is: price is not a continuous variable. Specifically, it has no derivative. Which makes a nonsense of Black-Scholes (?) option pricing
 

Offline tautech

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130079 on: August 17, 2022, 08:53:18 pm »
@tautech will go for that specialized premix husqvarna certified mix that does cost a bit more but comes without all those pesky additives good for the road but bad for the woods ...
Okay as you wish but can't be bothered with such BS here. I know what works, period !
What model Husky do you have, an Autotune one ?

Don't be bullied by this pollution BS as the little each of us use a saw has zip impact on the environment....whereas if we freeze to death think of all the extra lumber required for our deep sleep box or the gas required to crisp us to cinders.  :horse:
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 
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Online factory

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130080 on: August 17, 2022, 08:56:41 pm »
Found the restoring video of this thing: it is an HP 150A:


Thanks for posting that, I did watch the first part some time ago and skipped through most of it, as sanding & painting it was not very interesting to me, plus he painted the wrong color.  :palm:
Watched the other three parts last night, much better
David
Thank you so much for the link, just like you I had seen only the first episode but got a bit put off by it, now I watched the rest and they where quite good!
They did achieve one other thing for me: I'm totally put off buying a vacuum tube oscilloscope after seeing all that, I would not have the patience to repair such a beast!

And just as mansaxel writes here below another good reason is the electricity prices!
Currently as I'm writing this it's almost at 10SEK or around 90€/$ cents including taxes!!!

At least it has motivated me to setup a Home Assistant module that shuts off my water heater, and come winter when heating will be required the heater too based on hourly electricity rates:

...snip...

Topic discussion: Old TE is energy inefficient. Having large power costs influences the Addiction. Besides, electricity is sort of on-topic.  I hope.

It's definitely not a scope for Summer use, but this & many other hollow state TE double as fan heaters, 10MHz is enough for Winter isn't it? :-DD

The HP 150A I have, original owner must have been the US Navy, judging by all the labels.



The 6¼A fuse for operation from 115V.  :o



Took some pictures of the HV module, still waiting to be reunited with the scope, still has a couple of mixed dielectric? Sprague black beauties, that should probably be replaced.





The 150AR I have (first picture was taken by the last owner), original owner was N.P.L. , google that & you get National Physical Laboratory, but I can't confirm they were the N.P.L. on the label.





The Tek Museum are looking for a HP 150A for their collection. https://vintagetek.org/home-2/

David
« Last Edit: August 17, 2022, 09:39:26 pm by factory »
 
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130081 on: August 17, 2022, 09:03:01 pm »
idk wtf is going on, I bid 88.88, which was the winning bid, but somehow I'm not the winner? Fuck ebay, I'm done.

did someone else bid the same 88.88 but before you? Then the first bidder gets it. Had you set 88.89 it would be yours. Or sometimes you loose somtime the others win :o
Yes, sadly... bidding "clever amounts" like this can bite you in the arse. You're not the only one who likes to be clever.  ;)

If it's something you really want, then dig deep; until it hurts. That way when someone tops you by one copper, you can honestly say to yourself "It was too fucking much".

mnem
 :blah:

The correct amount to bid is that at which you will be equally unhappy whether you win or lose

Well, at least that went right then.
nuqDaq yuch Dapol?
Addiction count: Agilent-AVO-BlackStar-Brymen-Chauvin Arnoux-Fluke-GenRad-Hameg-HP-Keithley-IsoTech-Mastech-Megger-Metrix-Micronta-Racal-RFL-Siglent-Solartron-Tektronix-Thurlby-Time Electronics-TTi-UniT
 
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Offline Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130082 on: August 17, 2022, 09:11:43 pm »
@tautech will go for that specialized premix husqvarna certified mix that does cost a bit more but comes without all those pesky additives good for the road but bad for the woods ...
Okay as you wish but can't be bothered with such BS here. I know what works, period !
What model Husky do you have, an Autotune one ?

Don't be bullied by this pollution BS as the little each of us use a saw has zip impact on the environment....whereas if we freeze to death think of all the extra lumber required for our deep sleep box or the gas required to crisp us to cinders.  :horse:

I guess you misunderstood. Our husqvarna dealer is selling 2 stroke mixes which are guaranteed to be good for at least 2 years, without the ethanol in there, at the right mixture level.
it's 20€/5l, so I will just buy from them and not risk farting up the Husky by using the wrong mix.
 

Offline 25 CPS

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130083 on: August 17, 2022, 09:59:14 pm »
Now at 56 c/kWh. This is bloody insane.

Do you pay hourly rate or is it a generic high level? The peak prices were around those levels today, or even a bit higher, in SE4, the southernmost part of Sweden. Thankfully, we're in SE3, which is a little bit cheaper. (source: Nordpool)

I'm very much on the fence as to how I'm going to tackle next 12-month period; which agreement model I'm choosing, fixed, semi-rigid or full-floating. Full-floating requires instrumentation and some consumer control too. Tempting but do I have the drive to fix it what with the other 100s of things I need to do?  As someone wrote; "The dream of renewables in Germany mostly was natural gas through NordStream..."

Topic discussion: Old TE is energy inefficient. Having large power costs influences the Addiction. Besides, electricity is sort of on-topic.  I hope.

One thing I've heard in audio circles quite frequently is people who have tube amplifiers doing a seasonal changeout and running solid state equipment over the summer to avoid doubling up on electricity to run the equipment and then running the air conditioning more to remove the heat it generates.  I've done that myself and avoided running boatanchor test equipment during the summer for the same reason.  I don't know if this is a thing with ham radio operators and if the ones who have and use tube equipment substitute solid state when it's hot out.

The natural gas bill showed up today and the equal billing payments are 35.3% higher year over year.  What this does to hydro rates in terms of the effects it has on electricity prices due to the portion generated at natural gas fired power plants probably won't be known until late October when the time of use schedule changes and rates for the next six month block are announced.  If electricity prices get out of hand, when, how, and with what equipment the workshop gets run with is going to be up for review.  We'll see what happens.
 
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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130084 on: August 17, 2022, 11:01:35 pm »
... and he said he was selling three, one after the other. The first went for £75,  I got the second for £27, the third went for £85.

That's the easyJet pricing strategy. Hgh price a month in advance since you need to be there on that day for that planned event. High price a couple of days in advance, since you need to be there on that day for that unplanned event. Lowest price a week in advance, because it is a "wouldn't be nice if", it allows esayJet to plan, and you could change your mind.

For non-fleabay auctions the high-low-high isn't unusual. I guess the psychology is for the first ones "I can't miss getting one of these necessary items" and for the last ones "heck, I might miss one of these desireable items".
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130085 on: August 17, 2022, 11:05:14 pm »
Ok first simple dual transistor design complete and it's a piece of test gear! I will build it if I get some time on Saturday. It's a simple tester for panel meters at hamfests that will generate a 100uA and 1mA reasonably well calibrated current that can span around 1k to 3k or so in meter impedance. Will be used to test for FSD and sticky needles etc as I need panel meters for some projects. Is fairly immune to battery variations and uses 1.5mA of battery current worst case. Uses a basic Vbe current source.



Project two will be a new ESR meter containing glorious metal can transistors only as I dropped the old one the other day and conked the meter movement completely  :palm:
« Last Edit: August 17, 2022, 11:08:21 pm by bd139 »
 
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Offline Squarewave

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130086 on: August 17, 2022, 11:16:08 pm »
Ok first simple dual transistor design complete and it's a piece of test gear! I will build it if I get some time on Saturday. It's a simple tester for panel meters at hamfests radio rallies that will generate a 100uA and 1mA reasonably well calibrated current that can span around 1k to 3k or so in meter impedance. Will be used to test for FSD and sticky needles etc as I need panel meters for some projects. Is fairly immune to battery variations and uses 1.5mA of battery current worst case. Uses a basic Vbe current source.



Project two will be a new ESR meter containing glorious metal can transistors only as I dropped the old one the other day and conked the meter movement completely  :palm:

That's what I take a Time Electronics Micro Cal for  ;)
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130087 on: August 17, 2022, 11:22:37 pm »
I did think about buying something like that and decided that it was more fun to make one. Plus it’ll only cost about 2 quid
 

Offline Squarewave

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130088 on: August 17, 2022, 11:31:23 pm »
The Micro Cal was a good part of my TE addiction, but quite, yes, much fun to be had making something.
 

Offline med6753

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130089 on: August 18, 2022, 01:01:17 am »

Thank you so much for the link, just like you I had seen only the first episode but got a bit put off by it, now I watched the rest and they where quite good!
They did achieve one other thing for me: I'm totally put off buying a vacuum tube oscilloscope after seeing all that, I would not have the patience to repair such a beast!



On the contrary. There is nothing more satisfying than to transform this....



Into this....



And finally into this....

An old gray beard with an attitude.
 

Online TERRA Operative

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130090 on: August 18, 2022, 01:03:53 am »
Ok first simple dual transistor design complete and it's a piece of test gear! I will build it if I get some time on Saturday. It's a simple tester for panel meters at hamfests radio rallies that will generate a 100uA and 1mA reasonably well calibrated current that can span around 1k to 3k or so in meter impedance. Will be used to test for FSD and sticky needles etc as I need panel meters for some projects. Is fairly immune to battery variations and uses 1.5mA of battery current worst case. Uses a basic Vbe current source.



Project two will be a new ESR meter containing glorious metal can transistors only as I dropped the old one the other day and conked the meter movement completely  :palm:

That's what I take a Time Electronics Micro Cal for  ;)
Interesting that they have the ranges from high to low from the off position, instead of low to high.
I'd have designed it low to high to help prevent inadvertent overvolting of sensitive circuits if they are connected when turning the device on.
Where does all this test equipment keep coming from?!?

https://www.youtube.com/NearFarMedia/
 

Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130091 on: August 18, 2022, 02:40:11 am »

Thank you so much for the link, just like you I had seen only the first episode but got a bit put off by it, now I watched the rest and they where quite good!
They did achieve one other thing for me: I'm totally put off buying a vacuum tube oscilloscope after seeing all that, I would not have the patience to repair such a beast!



On the contrary. There is nothing more satisfying than to transform this....

   Into this....      And finally into this....   

As a bonus, med found out where his hamster ran away to hide... :-DD

mnem
*waiting quietly for MIL to arrive*
« Last Edit: August 18, 2022, 03:10:40 am by mnementh »
alt-codes work here:  alt-0128 = €  alt-156 = £  alt-0216 = Ø  alt-225 = ß  alt-230 = µ  alt-234 = Ω  alt-236 = ∞  alt-248 = °
 
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Offline Zoli

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130092 on: August 18, 2022, 04:19:57 am »
...
Yesterday I corrected the wonky needle problem  :bullshit:, it might still be knackered, as the zero adjust needs to be set all the way to one side, the plastic pin is broken off too, so it can't adjusted now it's back together. If I need to buy another complete meter movement I will.
...

...
David
If you have the tools/nerves, you can try to fix the pin in similar way as I've fixed the LCD support in my 8060A:
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg4237387/#msg4237387
 
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130093 on: August 18, 2022, 05:07:41 am »
I did think about buying something like that and decided that it was more fun to make one. Plus it’ll only cost about 2 quid

Doesn't a typical handheld DMM output precise currents of this nature on various ohms and diode test ranges..? Over an even wider impedance range too, I'll warrant...   :popcorn:
nuqDaq yuch Dapol?
Addiction count: Agilent-AVO-BlackStar-Brymen-Chauvin Arnoux-Fluke-GenRad-Hameg-HP-Keithley-IsoTech-Mastech-Megger-Metrix-Micronta-Racal-RFL-Siglent-Solartron-Tektronix-Thurlby-Time Electronics-TTi-UniT
 

Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130094 on: August 18, 2022, 05:22:55 am »
@tggzzz, I imagine the answer to this is "all kinds of nope":  https://autoshite.com/topic/34511-ebay-tat-volume-3/page/6567/?tab=comments#comment-2591870
nuqDaq yuch Dapol?
Addiction count: Agilent-AVO-BlackStar-Brymen-Chauvin Arnoux-Fluke-GenRad-Hameg-HP-Keithley-IsoTech-Mastech-Megger-Metrix-Micronta-Racal-RFL-Siglent-Solartron-Tektronix-Thurlby-Time Electronics-TTi-UniT
 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130095 on: August 18, 2022, 06:45:02 am »
I did think about buying something like that and decided that it was more fun to make one. Plus it’ll only cost about 2 quid

Doesn't a typical handheld DMM output precise currents of this nature on various ohms and diode test ranges..? Over an even wider impedance range too, I'll warrant...   :popcorn:

Unfortunately not the handheld ones generally. There’s a crude voltage source and series resistance with the resistor under test. Constant current should not be relied on. The bench meters tend to have current sources but aren’t very portable  :-DD
 
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130096 on: August 18, 2022, 07:28:06 am »
Ok first simple dual transistor design complete and it's a piece of test gear! I will build it if I get some time on Saturday. It's a simple tester for panel meters at hamfests that will generate a 100uA and 1mA reasonably well calibrated current that can span around 1k to 3k or so in meter impedance. Will be used to test for FSD and sticky needles etc as I need panel meters for some projects. Is fairly immune to battery variations and uses 1.5mA of battery current worst case. Uses a basic Vbe current source.



Project two will be a new ESR meter containing glorious metal can transistors only as I dropped the old one the other day and conked the meter movement completely  :palm:

Ah, one of my favourite circuits: dual transistor constant current source.  :-+  ;D
Personally, I'd add a 50µA and a 10µA output. I've seen panel meters with 50µA  and the 10µA can be used to check needle movement in the lower range.
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130097 on: August 18, 2022, 07:53:07 am »
... and he said he was selling three, one after the other. The first went for £75,  I got the second for £27, the third went for £85.

That's the easyJet pricing strategy. Hgh price a month in advance since you need to be there on that day for that planned event. High price a couple of days in advance, since you need to be there on that day for that unplanned event. Lowest price a week in advance, because it is a "wouldn't be nice if", it allows esayJet to plan, and you could change your mind.

For non-fleabay auctions the high-low-high isn't unusual. I guess the psychology is for the first ones "I can't miss getting one of these necessary items" and for the last ones "heck, I might miss one of these desireable items".

If someone is interested, this could be a nice thing to study:
The seller zhoefler (NAWTS) is selling some APEX PA12A power OpAmps.
Currently he sold eight of them, price range from EUR 40,94 to EUR 73,00.
All of them have been bought (very likely) by the same ebay customer.

Here are the details:
sold ones:
https://www.ebay.de/itm/134152319681
https://www.ebay.de/itm/134157443938
https://www.ebay.de/itm/403740925966
https://www.ebay.de/itm/403740926281
https://www.ebay.de/itm/134165669240
https://www.ebay.de/itm/134165669449
https://www.ebay.de/itm/134184982780
https://www.ebay.de/itm/403803662220

active ones:
https://www.ebay.de/itm/134184983542
https://www.ebay.de/itm/134188498366

And since this thread is worthless without a picture, here we go:


I'm not sure, if I can see here this easyJet pricing strategy.
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130098 on: August 18, 2022, 07:55:27 am »
Ok first simple dual transistor design complete and it's a piece of test gear! I will build it if I get some time on Saturday. It's a simple tester for panel meters at hamfests that will generate a 100uA and 1mA reasonably well calibrated current that can span around 1k to 3k or so in meter impedance. Will be used to test for FSD and sticky needles etc as I need panel meters for some projects. Is fairly immune to battery variations and uses 1.5mA of battery current worst case. Uses a basic Vbe current source.



Project two will be a new ESR meter containing glorious metal can transistors only as I dropped the old one the other day and conked the meter movement completely  :palm:

Ah, one of my favourite circuits: dual transistor constant current source.  :-+  ;D
Personally, I'd add a 50µA and a 10µA output. I've seen panel meters with 50µA  and the 10µA can be used to check needle movement in the lower range.

That's a good idea and I will add that as well :-+

Also gives me an excuse to buy a nice rotary switch too :-DD



Just got some good news. It's A-level results day here. Results through. Eldest got her first university choice so day of celebrations  ;D. She's off to study biochem. No soldering irons there but good luck to her  :-DD
 
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #130099 on: August 18, 2022, 08:06:26 am »
Just got some good news. It's A-level results day here. Results through. Eldest got her first university choice so day of celebrations  ;D. She's off to study biochem. No soldering irons there but good luck to her  :-DD

 :-+

Pity, she's not going into electronics.  :-\

but best wishes from my side and as much luck as she needs.  :D  :-+
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 
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