Test Equipment Anonymous (TEA) group therapy thread

[bd139]

I thought it was interesting how much older HP kit was present in that video.

[HalFET]

I thought it was interesting how much older HP kit was present in that video.

Makes sense for a cal lab though, you'd expect that the old equipment there is quite stable. (Their references have reached a nice flat platform.)

[Specmaster]

Not sure why. Avos are horrible things. Can't stand them. We had them in my university lab and a very annoying shortage of DMMs.

Bah, humbug !

Where else can you find something as cheap that measures 3KV ?

Thats a good point, though not sure if I trust the leads and probes at that level, not the older ones anyway.

What you must be careful of is the copycat AVO leads, easily spotted as they are stiffer PVC not the soft rubber of the originals.
Get originals and keep them clean and in good condition.

My Avo leads and probes are the originals and in very good condition but I've never been a fan of the probes though. The push in connection to the lead and the Long thin probes have always been to my mind, their weak spot. On the other hand I have a TMK700 meter that seems to have far better probes and I believe that will measure upto 2kv, I'll have to check it later, but it's probes are made from very thick plastic indeed.

Sent from my SM-J510FN using Tapatalk

[Specmaster]

Man I need to get cracking. I haven't purchased any test equipment for quite some time. I feel ashamed. Where's that Ebay link ... 

Just say what type of test gear you are in the mood for and i'm sure the nice people in here will supply the ebay links. If it says HP, Tek or Fluke on it it gets double points.

Haha Berni, sounds like the making of a Christmas Board game does that, points this and that, minus points if no one has made a purchase within so many days or weeks. Anyone up for making it into a game?

Sent from my SM-J510FN using Tapatalk

[tautech]

Not sure why. Avos are horrible things. Can't stand them. We had them in my university lab and a very annoying shortage of DMMs.

Bah, humbug !

Where else can you find something as cheap that measures 3KV ?

Thats a good point, though not sure if I trust the leads and probes at that level, not the older ones anyway.

What you must be careful of is the copycat AVO leads, easily spotted as they are stiffer PVC not the soft rubber of the originals.
Get originals and keep them clean and in good condition.

My Avo leads and probes are the originals and in very good condition but I've never been a fan of the probes though. The push in connection to the lead and the Long thin probes have always been to my mind, their weak spot.

Maybe so but for HV do you go around probing for measurements or connect first then power on ?
For safety's sake I acquired AVO's hook probe so that I could setup for a measurement totally hands free and then power the DUT on. The highest I've had to use an AVO for is 2750V, the EHT for a Telequipment D83 and buggered if I was gunna hold the probe, in fact any plain DMM probe.   

I don't use the AVO much but by gawd it's nice to know they were made for this HV stuff.
They're subjected to a 7KV flashover test, please tell me another affordable meter that is ?
When I need higher I've just got a Pintek 8 KV 1000:1 scope probe and even with the + 3% accuracy of a scope, that's near enough for me.

[Specmaster]

Maybe so but for HV do you go around probing for measurements or connect first then power on ?
For safety's sake I acquired AVO's hook probe so that I could setup for a measurement totally hands free and then power the DUT on. The highest I've had to use an AVO for is 2750V, the EHT for a Telequipment D83 and buggered if I was gunna hold the probe, in fact any plain DMM probe.   

I don't use the AVO much but by gawd it's nice to know they were made for this HV stuff.
They're subjected to a 7KV flashover test, please tell me another affordable meter that is ?
When I need higher I've just got a Pintek 8 KV 1000:1 scope probe and even with the + 3% accuracy of a scope, that's near enough for me.

In some locations it is not possible to connect hands free.
Just checked the TMK700 and was surprised to discover that will measure 5Kv AC and DC, photos attached that show this and also the very thick insulation on the probes.

[bd139]

Not sure I'd trust it. My HV probe looks like this. Granted it goes up to 40KV but I'd rather be safe than sorry.

[tggzzz]

For safety's sake I acquired AVO's hook probe so that I could setup for a measurement totally hands free and then power the DUT on. The highest I've had to use an AVO for is 2750V, the EHT for a Telequipment D83 and buggered if I was gunna hold the probe, in fact any plain DMM probe.   

Scared can be good.

I measured the 2.7kV two ways: with a Simpson Avo 8 equivalent, and with 3*33M+100k resistor acting as a potential divider and a normal handheld DMM. Hands kept well away!

No, I wouldn't recommend that technique, and now have a 12kV scope probe

[bd139]

Nice to see a D83 mentioned here. Good scopes with a nice sized screen. Poor man's Tek 7000. Had one years ago I paid £5 for from Gumtree because it had an odd power connector. Stuffed an IEC socket on it. Worked fine!

[Specmaster]

I have a very healthy respect for HV and so unless I really need to know, I just won't ever go near it. I have so far not used my meters for anything higher 500V and if I had to then I'd invest I think in a proper probe for the job. I know that I'm pushing a few years,. but still I have desire to risk speeding my departure from this world for the next I can assure you.

I have sat through too many safety films and have seen what high energy and HV can do to a person to take unnecessary risks that I don't have to do.

[bd139]

To be honest, CRT bias just stings a bit. I've had a couple of 7KV-ish zaps over the years (thanks Philips!) and it feels like someone has slapped your hand. It's not all that notable. Remember when you take a synthetic jumper off by pulling it over you, you're generating more than a few KV there as well, just a lot less current. Do it in the dark and let your eyes adjust and you can see the sparks.

The killer is mains potential and/or if it goes across your chest. The "stick one hand in the pocket" advice is good.

Clearly avoidance and using proper safety equipment is always the best tactic however which is why I invested in CAT rated meters, cables and an HV probe.

[Specmaster]

Agreed, but if I can avoid shocks of any nature then I will. 

[bd139]

Sometimes it's fun! I had one of those 160-in-1 kits in the very early 1980s from my parents and I regularly wired up a relay oscillator and zapped my sister with the inductive kickback 

[Specmaster]

You'd better hope that she dosent get one of those kits herself and rig up a few interesting ways zap you back as payback for your passed misdemeanors that she had to endue 

[Berni]

Oh yes relay oscillator zappers are always fun. They can sometimes pack quite a punch too.

[Specmaster]

I used to work with a chap who would happily touch the grab spark plug leads and ground at the same time and stop the engine dead.                                                                                                           

[tautech]

Nice to see a D83 mentioned here. Good scopes with a nice sized screen. Poor man's Tek 7000. Had one years ago I paid £5 for from Gumtree because it had an odd power connector. Stuffed an IEC socket on it. Worked fine!

Yep, gorgeous crisp display and a very capable CRO although getting long in the tooth now so reliability is an issue.

I have a very healthy respect for HV and so unless I really need to know, I just won't ever go near it. I have so far not used my meters for anything higher 500V and if I had to then I'd invest I think in a proper probe for the job. I know that I'm pushing a few years,. but still I have desire to risk speeding my departure from this world for the next I can assure you.

I have sat through too many safety films and have seen what high energy and HV can do to a person to take unnecessary risks that I don't have to do.

First decent zap I had (other than magnetos  ) was a HT tube PSU I made from stuff dad had lying around, 700 VAC plate voltage on a 5Z4 sent me across the bedroom. I was only 12 or 13 so the impression it left has served me well all these years......or maybe that's what's wrong with me. 

A few years on when I worked on small motors the guy I worked with had great delight in charging ignition caps with an ignition tester and leaving them on the bench for any poor unsuspecting souls. Bastard !

[bd139]

Talking of high voltages and HT, I fixed the 2225. RS delivery arrived so replaced nearly all the power supply capacitors. Still buzzing and arcing. About 20 minutes after the sadness from this event wore off, the rest arrived from CPC and were installed. Powered it up and silence. I thought to myself "oh shit I've killed it". I sat there waiting for the smell of magic smoke and none came so I hit the front panel and noticed a faint trace. I had knocked the intensity down.

No arcing, crisp trace, good as new! Going to keep this one as it's a nice little scope.

Anyway it's done now. Body count minus the 2 missing as I did them at the weekend:



I reckon the bastards that were causing the problem were the two little Philips 030's. They got replaced like for like with Vishay 030's.

Due to minimum order quantities I've got nearly enough caps spare now to do another 2225 if one comes along!

[Specmaster]

Yep, been there before, send you off in a spin until you start thinking, lets play with the controls a bit and see what happen and then bingo 

I seem remember a certain lovely 475 that was going to the grave with you, but thats gone, so I expect that in a couple of weeks this one will be gone as well 

Mystic Meg has a 465B for sale, has a trace and all.......

[Specmaster]

I thought Mouser was in High Wycombe? I have just had an email saying my order of caps and resistors etc will be with me on Thursday, which is taking longer then I expected. They also gave a tracking link and myself seems to be coming from Memphis, Tennessee, and has just been picked up from GRAND PRAIRIE, TX. 

[bd139]

Their office is there. They ship from the US as far as I know. I haven’t used them before. Usually bend over and take the Farnell buggering.

[Cerebus]

I had an SMPS to recap last week and getting the right ESR and case size meant a bit more searching than usual. I ended up getting the set I needed from RS because they were 1/2 to 2/3 the price Farnell were asking on the particular caps I needed. That's not an across the board evaluation of the comparative pricing between the two but it must indicate that something's going on. I spent around £10 with RS where I would have spent around £20 with Farnell, the latter pushed up a bit extra by the minimum pack size on one particular cap, it would have been about £16-17 if they'd had the same pack size as RS.

[Specmaster]

Their office is there. They ship from the US as far as I know. I haven’t used them before. Usually bend over and take the Farnell buggering.

Whatever floats yer boat, don't it make yer eyes water 

[bd139]

I had an SMPS to recap last week and getting the right ESR and case size meant a bit more searching than usual. I ended up getting the set I needed from RS because they were 1/2 to 2/3 the price Farnell were asking on the particular caps I needed. That's not an across the board evaluation of the comparative pricing between the two but it must indicate that something's going on. I spent around £10 with RS where I would have spent around £20 with Farnell, the latter pushed up a bit extra by the minimum pack size on one particular cap, it would have been about £16-17 if they'd had the same pack size as RS.

That’s quite normal. I tend to try for CPC and RS first. Takes me longer to select parts then fix stuff.

[Specmaster]

I had an SMPS to recap last week and getting the right ESR and case size meant a bit more searching than usual. I ended up getting the set I needed from RS because they were 1/2 to 2/3 the price Farnell were asking on the particular caps I needed. That's not an across the board evaluation of the comparative pricing between the two but it must indicate that something's going on. I spent around £10 with RS where I would have spent around £20 with Farnell, the latter pushed up a bit extra by the minimum pack size on one particular cap, it would have been about £16-17 if they'd had the same pack size as RS.

I wanted some caps and 1% and .1% resistors last week and neither could satisfy my requirements and I thought that RS offering was pitiful really.