Test Equipment Anonymous (TEA) group therapy thread

[worsthorse]

The harvest is full and I feel that this HP engineer is very partial to Tektronix equipment. 
 I just repaired 485, in fact it has no malfunctions, just a human error.  The original master short-circuited a line that triggered B to logic control.  As a result, B trigger and 5, 2, and 1nS cannot be triggered.  Now it is completely alive.

Yeah, you should see his collection of spectrum analyzers. Damn.

This 485 project will require me to use two as part mules to fix the third given the stuff that's already been taken out of them.

And finding and easily addressable [someone else's] human error as the source of a problem that is easy to fix is just about the best kind of problem to find.   

[0culus]

@worsthorse looks like you've now more than filled the void left by that 184 parts unit.  Happy to report that my 184 seems to be ticking along fine after repairs. Hopefully if I can get this 585A up and running I can put the 184 to good use verifying timebase performance.

[med6753]

0-11. 

Continuing my visual inspect of the 585A...I may have identified a capacitor in the vertical amplifier that is beginning to vomit it's guts.

Something you should be aware of. This is from Stan Griffith's book. Chances are your 585A is going to have at least some of this issue.

I purchased a copy of his book from vintagetek's ebay store not long before he passed, and had read about this...gotta get it powered up first to see if cathode interface will be an issue. 

Tap foot...waiting.  What's taking you so long? 

Edit....Oops, didn't see your update on the possible shorted diodes.

But still...we wanna see smoke. 

[med6753]

The harvest is full and I feel that this HP engineer is very partial to Tektronix equipment. 
 I just repaired 485, in fact it has no malfunctions, just a human error.  The original master short-circuited a line that triggered B to logic control.  As a result, B trigger and 5, 2, and 1nS cannot be triggered.  Now it is completely alive.

Yeah, you should see his collection of spectrum analyzers. Damn.

This 485 project will require me to use two as part mules to fix the third given the stuff that's already been taken out of them.

And finding and easily addressable [someone else's] human error as the source of a problem that is easy to fix is just about the best kind of problem to find.   

The HP engineer knew what we know. Tek scopes rule and HP scopes drool. 

Conversely,  HP SA's rule and Tek SA's drool. 

[0culus]

0-11. 

Continuing my visual inspect of the 585A...I may have identified a capacitor in the vertical amplifier that is beginning to vomit it's guts.

Something you should be aware of. This is from Stan Griffith's book. Chances are your 585A is going to have at least some of this issue.

I purchased a copy of his book from vintagetek's ebay store not long before he passed, and had read about this...gotta get it powered up first to see if cathode interface will be an issue. 

Tap foot...waiting.  What's taking you so long? 

Edit....Oops, didn't see your update on the possible shorted diodes.

But still...we wanna see smoke. 

Since I now know what's wrong, I don't see the point in blasting a fuse when the suitable replacement diodes are cheaper than dirt on Digikey.  

[med6753]

0-11. 

Continuing my visual inspect of the 585A...I may have identified a capacitor in the vertical amplifier that is beginning to vomit it's guts.

Something you should be aware of. This is from Stan Griffith's book. Chances are your 585A is going to have at least some of this issue.

I purchased a copy of his book from vintagetek's ebay store not long before he passed, and had read about this...gotta get it powered up first to see if cathode interface will be an issue. 

Tap foot...waiting.  What's taking you so long? 

Edit....Oops, didn't see your update on the possible shorted diodes.

But still...we wanna see smoke. 

Since I now know what's wrong, I don't see the point in blasting a fuse when the suitable replacement diodes are cheaper than dirt on Digikey.  

Couldn't you just stick in a suitable 1N400X and be done with it?

And for minor repairs you don't absolutely have to have the silver bearing solder on those terminal strips. Just be careful. I've done it with good results.

[0culus]

0-11. 

Continuing my visual inspect of the 585A...I may have identified a capacitor in the vertical amplifier that is beginning to vomit it's guts.

Something you should be aware of. This is from Stan Griffith's book. Chances are your 585A is going to have at least some of this issue.

I purchased a copy of his book from vintagetek's ebay store not long before he passed, and had read about this...gotta get it powered up first to see if cathode interface will be an issue. 

Tap foot...waiting.  What's taking you so long? 

Edit....Oops, didn't see your update on the possible shorted diodes.

But still...we wanna see smoke. 

Since I now know what's wrong, I don't see the point in blasting a fuse when the suitable replacement diodes are cheaper than dirt on Digikey.  

Couldn't you just stick in a suitable 1N400X and be done with it?

And for minor repairs you don't absolutely have to have the silver bearing solder on those terminal strips. Just be careful. I've done it with good results.

Yes, but I don't have one with a high enough voltage rating on hand. I do actually have some silver bearing solder, that was in the 184 when I got it. 

[med6753]

Yes, but I don't have one with a high enough voltage rating on hand. I do actually have some silver bearing solder, that was in the 184 when I got it. 

I hear you. My Type 561B resto was held up almost a week for want of a small signal diode that could not be crossed with a 1N4148....which I have about 50 on hand. 

[Ice-Tea]

Back from my trip south... I visited with a ex-HP engineer who collected a whole lot of test gear over the years. Interesting guy with some good stories and a warehouse space that was packed with TE and components. To say the place was a warren is an understatement. Based on my phone conversations with him, I didn't have high expectations; it was more like buying a raffle ticket. Here's what I came back with:



A TM504 frame, a bunch of TM plugins, including several that I've been searching for, and three 485s.  Oh yeah, a HP programmable attenuator, a manual attenuator, and a directional coupler.  Did any of it work? Other than physically inspecting the plugins, I had no idea. Like I said, treasure hunt.

Did some preliminary testing when I got home. The three 485s each have different issues or missing parts but probably can be merged to make one good unit.  The TM405 frame, along with five of the plugins, works. Six of the plugins don't but none are damaged and therefore, probably repairable.  Given what I paid for the pile, not a surprise and, all in all, well worth the trip.

Now that I've been through the place once, I will likely make another trip to garner a few more goodies for my lab.

Dang!

[Specmaster]

0-11. 

Continuing my visual inspect of the 585A...I may have identified a capacitor in the vertical amplifier that is beginning to vomit it's guts.

Something you should be aware of. This is from Stan Griffith's book. Chances are your 585A is going to have at least some of this issue.

I purchased a copy of his book from vintagetek's ebay store not long before he passed, and had read about this...gotta get it powered up first to see if cathode interface will be an issue. 

Tap foot...waiting.  What's taking you so long? 

Edit....Oops, didn't see your update on the possible shorted diodes.

But still...we wanna see smoke. 

Since I now know what's wrong, I don't see the point in blasting a fuse when the suitable replacement diodes are cheaper than dirt on Digikey.  

Couldn't you just stick in a suitable 1N400X and be done with it?

And for minor repairs you don't absolutely have to have the silver bearing solder on those terminal strips. Just be careful. I've done it with good results.

Yes, but I don't have one with a high enough voltage rating on hand. I do actually have some silver bearing solder, that was in the 184 when I got it. 

Yeah its my understanding that always included a small roll of said silver solder inside them for future repairers to use to maintain the purity.

[tonyalbus]

Is it a Philips, is it a Fluke, or both... i found 3 types and i own one... its actualy better then i thought.

What year did the Fluke/Philips relationship start?

I have an old Fluke 8505a that also displays the "Fluke Philips Alliance" sticker on the top.

In 1987, Fluke partnered with the Dutch electronics manufacturer Philips. Together, the companies developed the scopemeter, an instrument combining features of an oscilloscope and a multimeter. Fluke purchased the testing and measurements division of Philips in 1993 for $41.8 millions.[2] The Philips PM series of measurement instruments was rebranded as Fluke.

[bd139]

Had no idea it was that low that sale including inflation. That’s pretty scarily cheap. The company I work for sold out for an order of magnitude more than that a while back and we have less people and don’t produce any physical goods. It’s insane.

[Specmaster]

So based on information, my Fluke PM3390B scope is really a Phillips just rebranded?

[bd139]

Yeah that’s basically it. You can see a lot of the classic Philips design on the boards as well.

[tonyalbus]

So based on information, my Fluke PM3390B scope is really a Phillips just rebranded?

Philips has always/mostly use PM (Philips Measure?) in there types.... so yes that could be the case....sorry
Well we Dutch sometimes make fun of Philips, not everything they did was good. (specialy there consumer electronics tryouts)
There slogen,: Lets make thing better, was often, : Lets make better things.
But to be honest, there professonial and medical stuff is good.

[med6753]

Yeah its my understanding that always included a small roll of said silver solder inside them for future repairers to use to maintain the purity.

If a Tek instrument used the ceramic strips yes, there was a small roll of silver solder included. Problem is after 40 - 50 odds years the rolls disappeared or got used up. So far of all my vintage Tek's here only the Type 191 Signal Generator still had a roll of the silver solder on the chassis.

Edit, as long as the strip currently has some silver solder content and you need to add a component mixing in some 60/40 solder to get a good connection is acceptable.

[Specmaster]

Right, here we go after an hour of scrubbing the PCB of Black Star 4503 to remove even the merest hint of any flux residue with cotton buds dipped in 70% IPA, toothbrush is too wide and was bending things in order to make contact with the board, so I used cotton buds. I can now declare this instrument fit for active service and will shortly be reporting for active duty on the front line when I reshuffle my stacks. It has been a long and hard battle to get this lovely old instrument restored and ready for duty once again and while there are a couple of very minor discrepancies in some readings, this is I believe down to areas where the auto ranging is considering switching to the next range, and is a little twitchy in that zone with last digits flicking up/down which is entirely understandable as all my other meters are similarly affected in those zones.
Below are photos of measuring 1mV, 10mV, 100mV, 1V, 2.5V, 5V, 7.5V, 10V and lastly 100V and it's not too shabby at all, I think you'll agree.



   

[SilverSolder]

So based on information, my Fluke PM3390B scope is really a Phillips just rebranded?

Philips has always/mostly use PM (Philips Measure?) in there types.... so yes that could be the case....sorry
Well we Dutch sometimes make fun of Philips, not everything they did was good. (specialy there consumer electronics tryouts)
There slogen,: Lets make thing better, was often, : Lets make better things.
But to be honest, there professonial and medical stuff is good.

Philips TV sets were highly regarded in the past, I don't know the situation today.

[med6753]

So as long as the "V" LED is on but the "AC" LED is off I assume that means it's in DCV, correct? That seems a little odd.

[SilverSolder]

Had no idea it was that low that sale including inflation. That’s pretty scarily cheap. The company I work for sold out for an order of magnitude more than that a while back and we have less people and don’t produce any physical goods. It’s insane.

Until recently, even an ice cream van could be IPO'd on the stock exchange for $Bn+ ! 

[AVGresponding]

So as long as the "V" LED is on but the "AC" LED is off I assume that means it's in DCV, correct? That seems a little odd.

Yes.

It makes sense if you think about it; the AC LED can apply to both volts and current ranges.

[med6753]

So as long as the "V" LED is on but the "AC" LED is off I assume that means it's in DCV, correct? That seems a little odd.

Yes.

It makes sense if you think about it; the AC LED can apply to both volts and current ranges.

OK, that part makes sense but the overall design does not. Every multimeter that I've come across either by switch selection or indicator very clearly says "DCV" when enabled. That multimeter has LED's for a myriad of functions that do everything but tie your shoes. How much additional would it have cost to add an LED that stated "DC"? Even if it powers up default DCV it should still say so. You know what happens when you  ass-u-me. It allows Murphy to intervene big time.     

[PA0PBZ]

Philips TV sets were highly regarded in the past, I don't know the situation today.

They sold the name in 2011 to the Chinese TP Vision, they still make TV's branded Philips.
I have no idea about the quality really, I suppose they are not bad.

[SilverSolder]

Philips TV sets were highly regarded in the past, I don't know the situation today.

They sold the name in 2011 to the Chinese TP Vision, they still make TV's branded Philips.
I have no idea about the quality really, I suppose they are not bad.

If they are smart, they will make the products good enough to maintain the reputation of the brand.   E.g. car makers are generally very conscious of this...  with a few notable exceptions!

[Specmaster]

So as long as the "V" LED is on but the "AC" LED is off I assume that means it's in DCV, correct? That seems a little odd.

Yes.

It makes sense if you think about it; the AC LED can apply to both volts and current ranges.

OK, that part makes sense but the overall design does not. Every multimeter that I've come across either by switch selection or indicator very clearly says "DCV" when enabled. That multimeter has LED's for a myriad of functions that do everything but tie your shoes. How much additional would it have cost to add an LED that stated "DC"? Even if it powers up default DCV it should still say so. You know what happens when you  ass-u-me. It allows Murphy to intervene big time.     

The thing with the 4503 that can catch people out is that it will always default on switch on to the last setting it was on at switch off. That means it is possible to whack say DCV straight across the AC, Resistance or Current inputs, this is a design fault in this meter, but if one adopts the same attitude that you do with a manual switcher, then you will check the range its on before you probe anything. This is what I do with my 2 manual switches, the 1905a and the 3466A, both of which have physical buttons to indicate the range but the 4503 has LED's, but the saving grace is that it does have some great input protection built in.