Test Equipment Anonymous (TEA) group therapy thread

[bd139]

Thanks. No explosion or heating after 10 minutes 

Just grabbed a hooky looking Hameg HM203-5 off ebay to use as a display for this SA. As much as I like 'em, neither of the digital scopes I own can cope with such a duty effectively 

[med6753]

Thanks. No explosion or heating after 10 minutes 

Just grabbed a hooky looking Hameg HM203-5 off ebay to use as a display for this SA. As much as I like 'em, neither of the digital scopes I own can cope with such a duty effectively 

If it were to burst into flames it would just be a normal day in your domain. 

[bd139]

Hey that's your title now 

[med6753]

Hey that's your title now 

What you talking about? I haven't had any flames since May. 

[Saskia]

yer not trying hard enuff ..

[BU508A]

Blimey!

This morning I got a heads-up email from the German ebay ads (ebay Kleinanzeigen).
A 34401A has been listed. I checked and was really surprised.
A used but working 34401A without the handle for EUR 87.-   
Wrote immediatly to the seller but as you can imagine there were lots of people interested in.
Now it's gone and I didn't have a chance for bidding or something. 

Wow! 87 Euro. Gone... 

[bd139]

That was crazy cheap!

One went here for £50 a while ago round the corner from me from TICS which was pissing error codes. I should have jumped on that

[Specmaster]

Possible it was beyond economical repair anyway, but we'll never know for certain now 

[bd139]

Was worth it for parts at that price TBH

[BU508A]

Possible it was beyond economical repair anyway, but we'll never know for certain now 

The ad was saying "fully functional" and the pictures I've seen suggested the same.
But yes, we'll never know now ...

Sometimes you lose, sometimes the others win. 

[med6753]

Started troubleshooting the Type 1A2 plug-in by doing some static testing hoping to get lucky. Swapped out the 6DJ8 output tube and checked all the transistors in view. No joy. All good. Also checked those power resistors in the background as well as some diodes underside. Didn't get lucky. So I guess I'm going to have to install it in the 535A and jackass it on it's side. Whoopie. 

[0culus]

I want to measure the storage time of some fast diodes, but none of the pulse generators I have are fast enough.  I have a Colby PG1000A 1 GHz pulse generator with 200ps rise and fall times, but it does not have enough output amplitude swing to make diode measurements, so I bought this HP 8082A pulse generator I bought on fleabay for parts or repair. 

It has a broken power switch and light, but seems to be somewhat working.  The rise and fall times are excellent (<1ns).  However the output amplitude is a bit low (4.5V vs 5V).  I will work on it, record the troubleshooting and repairs, and post a video when I am done.

Here is a preliminary look at it.  Click on the imaged for much larger versions.







Chris

Ha, I just got one of those myself. It seems to be in working order so let me know if you want to see any waveforms for comparison.  Really great pulser though. Worth fixing.

[0culus]

Started troubleshooting the Type 1A2 plug-in by doing some static testing hoping to get lucky. Swapped out the 6DJ8 output tube and checked all the transistors in view. No joy. All good. Also checked those power resistors in the background as well as some diodes underside. Didn't get lucky. So I guess I'm going to have to install it in the 535A and jackass it on it's side. Whoopie. 

 Dread having to sit the 585A on its side so I can get to the bottom of a plug-in. I now have a kit to build a flexible Tek 7000 series plugin adapter, bet something similar could be done for these plug-ins.

[med6753]

 Dread having to sit the 585A on its side so I can get to the bottom of a plug-in. I now have a kit to build a flexible Tek 7000 series plugin adapter, bet something similar could be done for these plug-ins.

I don't know if you've had to do it with your 585A but trust me, it ain't fun.

Since both channels of the 1A2 are affected I suspect the problem lies with this voltage divider circuit. It's one of the first items I'm going to check.

[0culus]

 Dread having to sit the 585A on its side so I can get to the bottom of a plug-in. I now have a kit to build a flexible Tek 7000 series plugin adapter, bet something similar could be done for these plug-ins.

I don't know if you've had to do it with your 585A but trust me, it ain't fun.

Since both channels of the 1A2 are affected I suspect the problem lies with this voltage divider circuit. It's one of the first items I'm going to check.

I haven’t yet for plugin work, but I had to manipulate it up and down several times when I was diagnosing the original short that I ultimately fixed by replacing two diodes in the rectifiers. The recommended power supply test points for checking resistances are on the bottom of course. 

[AVGresponding]

Received an 8050A today, sold as "used". I believe a more accurate term would be "borked".

No meaningful readings on any range, looks like it's had some sort of HV encounter. Might just send it back, as I don't want to add to the repair conga-line. On the plus side, the display is good...



Update on the Keithley: two messages from the seller;

I got to some page and I think I got to accept the payment and got this message" We’ve reviewed your transaction and your payment is now eligible for release. Your funds will be available in your PayPal account within 24 hours."
Did anything happen at your end which will suggest that the payment will go through now?
Sorry for this delay but I don't sell that much on ebay and don't know all the steps that I need to go through ..and ebay don't seem to make it easy for you to know what is happening.

and then

I also open a case for this because I don't think this is going to work. I hade a closer look and the payment that I accepted was from the previous listing of this item which somebody bought and got similar problems with payment then change his mind and cancelled the transaction. Don't know why the option of accepting payment was still there after the transaction was cancelled.
I don't know why they make it so complicated and obfuscate info on what you need to do to make a transaction happen.
I try to contact eBay customer service ...all I get is an automated message that tells me to go and find help online which is total BS ...no option to speak to anybody.
I really don't know what to do here and what is going on.
I will wait until tomorrow ...maybe I get some help from eBay on this. this is getting really frustrating.

Seriously? I think the fkk not.

Got eBay to call me straight away, took them less than a minute. The assure me there's no way I will get an unpaid marker on my account as they can see I paid, and the problem is on the seller's end.

I'll confess I'm starting to get a bit annoyed.

[tonyalbus]

Received an 8050A today, sold as "used". I believe a more accurate term would be "borked".

Think i have a 8050A around in my pile if you need comparison material when you decide to repair.

[bd139]

Received an 8050A today, sold as "used". I believe a more accurate term would be "borked".

No meaningful readings on any range, looks like it's had some sort of HV encounter. Might just send it back, as I don't want to add to the repair conga-line. On the plus side, the display is good...

Check power supply on it. Sometimes it's a dead simple fix on them.

Update on the Keithley: two messages from the seller;[/color][/size][/b]

I got to some page and I think I got to accept the payment and got this message" We’ve reviewed your transaction and your payment is now eligible for release. Your funds will be available in your PayPal account within 24 hours."
Did anything happen at your end which will suggest that the payment will go through now?
Sorry for this delay but I don't sell that much on ebay and don't know all the steps that I need to go through ..and ebay don't seem to make it easy for you to know what is happening.

and then

I also open a case for this because I don't think this is going to work. I hade a closer look and the payment that I accepted was from the previous listing of this item which somebody bought and got similar problems with payment then change his mind and cancelled the transaction. Don't know why the option of accepting payment was still there after the transaction was cancelled.
I don't know why they make it so complicated and obfuscate info on what you need to do to make a transaction happen.
I try to contact eBay customer service ...all I get is an automated message that tells me to go and find help online which is total BS ...no option to speak to anybody.
I really don't know what to do here and what is going on.
I will wait until tomorrow ...maybe I get some help from eBay on this. this is getting really frustrating.

Seriously? I think the fkk not.

Got eBay to call me straight away, took them less than a minute. The assure me there's no way I will get an unpaid marker on my account as they can see I paid, and the problem is on the seller's end.

I'll confess I'm starting to get a bit annoyed.

I think the guy is just an epic fucktard. I'd try and get the money back.

[tggzzz]

Update on the Keithley: two messages from the seller;[/color][/size][/b]

I got to some page and I think I got to accept the payment and got this message" We’ve reviewed your transaction and your payment is now eligible for release. Your funds will be available in your PayPal account within 24 hours."
Did anything happen at your end which will suggest that the payment will go through now?
Sorry for this delay but I don't sell that much on ebay and don't know all the steps that I need to go through ..and ebay don't seem to make it easy for you to know what is happening.

and then

I also open a case for this because I don't think this is going to work. I hade a closer look and the payment that I accepted was from the previous listing of this item which somebody bought and got similar problems with payment then change his mind and cancelled the transaction. Don't know why the option of accepting payment was still there after the transaction was cancelled.
I don't know why they make it so complicated and obfuscate info on what you need to do to make a transaction happen.
I try to contact eBay customer service ...all I get is an automated message that tells me to go and find help online which is total BS ...no option to speak to anybody.
I really don't know what to do here and what is going on.
I will wait until tomorrow ...maybe I get some help from eBay on this. this is getting really frustrating.

Seriously? I think the fkk not.

Got eBay to call me straight away, took them less than a minute. The assure me there's no way I will get an unpaid marker on my account as they can see I paid, and the problem is on the seller's end.

I'll confess I'm starting to get a bit annoyed.

That is indeed ridiculous.

At the very least the vendor is incompetent; anybody with any sense would use a very cheap sale (preferably to a relative) to ensure the basic selling process worked and they understood it.

In your shoes I would be considering that the vendor is trying to run down some clock or other. I'd be looking for a way to reclaim my money; some purchases aren't worth the hassle.

[Robert763]

So I bid an won a HP DMM on ebay, not because I need another DMM or that it's anything special, a E2373A.
Just because I'm a TEA and my only other HP handheld DMM is a 3476 "tricorder" 
 

[AVGresponding]

Received an 8050A today, sold as "used". I believe a more accurate term would be "borked".

No meaningful readings on any range, looks like it's had some sort of HV encounter. Might just send it back, as I don't want to add to the repair conga-line. On the plus side, the display is good...

Check power supply on it. Sometimes it's a dead simple fix on them.

"Thou shalt measure voltages."

Haha, power supply is fine, sadly. It was likely to be as it performs the impedance check ok, so the cpu is ticking at least.

Symptoms are wandering/OL readings in all ranges. Suspect something is all melty either in the ADC or its input filtering. Need to check the waveforms in the service manual and then start hunting for opens and shorts. Nothing visible, hence my belief its over-voltage rather than over-current this time. Also the fuses are the right value, the 10x38 looks like it might be the original one, the label and glue are yellowed with age.

Received an 8050A today, sold as "used". I believe a more accurate term would be "borked".

Think i have a 8050A around in my pile if you need comparison material when you decide to repair.

You can't force me to fix it, dammit!   

 

[bd139]

Received an 8050A today, sold as "used". I believe a more accurate term would be "borked".

No meaningful readings on any range, looks like it's had some sort of HV encounter. Might just send it back, as I don't want to add to the repair conga-line. On the plus side, the display is good...

Check power supply on it. Sometimes it's a dead simple fix on them.

"Thou shalt measure voltages."

Haha, power supply is fine, sadly. It was likely to be as it performs the impedance check ok, so the cpu is ticking at least.

Symptoms are wandering/OL readings in all ranges. Suspect something is all melty either in the ADC or its input filtering. Need to check the waveforms in the service manual and then start hunting for opens and shorts. Nothing visible, hence my belief its over-voltage rather than over-current this time. Also the fuses are the right value, the 10x38 looks like it might be the original one, the label and glue are yellowed with age.

Check Q1 and Q2 aren't borked and clean the switches out. They are the "front most" two transistors, one in the switches, one near the input jacks. I've had at least 2 8050A's where one of them is buggered or the switches are dirty that did that and worked fine afterwards.

[Specmaster]

@AVGresponding Regards to the seller situation, I'm still smelling that nasty whiff under my nose of BS. Come on, I'm sure that you have sold on eBay as well and when using PayPal, they don't tell you that funds are not yet cleared or will be in your account within so many hours. What happens is that the request for payment is fully automatic, the buyer clicks on the link to pay via PayPal and the rest is down to the buyer, who cannot screw it up. The seller, once the buyer has paid via PayPal, gets an email from PayPal telling him that you have paid and to dispatch the goods to the buyer.

The seller does not get the money transferred to his bank until he requests to transfer some or all of the money to his registered bank account and then it is done within minutes. I don't buy this bullshit that he is telling you for a single minute, it has all the hallmarks of a scam written all over it, especially seeing that he has already had a previous buyer for this meter, who it would seem, backed out of the deal, maybe they too were getting all this BS about not being able to get access to the money etc.

Run away and fight another day is my gut reaction to this deal.

[AVGresponding]

Check Q1 and Q2 aren't borked and clean the switches out. They are the "front most" two transistors, one in the switches, one near the input jacks. I've had at least 2 8050A's where one of them is buggered or the switches are dirty that did that and worked fine afterwards.

Q1 & 2 are good. Switches all bell out good. Keep trying, I'll stick to my ADC theory, just cba to bugger about with scopes right now as I'm functioning on 1 hour of sleep in the last 2 days...

 

[tonyalbus]

Pull out when you don't trust....... saves you a lot of trouble......
could be a life motto