Test Equipment Anonymous (TEA) group therapy thread

[factory]

HP report,
8405a, still has intact factory stickers, a26 is a riser card ( ) and there is a wasps nest on the freq range switch. One of the probe tips, channel a, has broken off, it only has two feet and in general the thing is FILTHY.
HP1645B Didn't open due to special screw head, will have to buy screwdriver or find one. Has a copy of its os disc and i've found one probe, except it isn't quite a probe its just a pin header to pin header cable.
How screwed am i on these two?

hey neo.  when you find a T10 torx driver and get the cover off that logic analyzer I would appreciate a picture of the power supply.


just curious that's all.


ps  that hickok is a thing of beauty.  have a buddy with two of them and he swears by 'em.   guess anyone who owns a frickin' 608 boatanchor needs a good tubetester.


pps  not sure however why anyone needs a crt rejuvenator.   always considered them to be snake oil.

Isn't it a CRT tester too? Kind of useful if you restore vintage TV's to find out if the picture tube picture bulb is any good before spending a lot of time/money on it. See some of Shango066 video's on youtube, he sometimes takes one (powered from a inverter & battery) with him to see if they are worth buying/saving or dragging out of abandoned mine waste dumps.

David

edit: Here is a recent-ish video with on picture bulb testing by Shango066;

https://youtu.be/LZvirB89cxU

[factory]

Saw this go the other day for £140. What the fuck was whoever bought it thinking? All the other items the ebayer were selling were wet and rotten and rusting. They didn't even bother to clean off the standing water that was all over half of the items. Just literally tipped them up for a photo and probably threw them back in the shed !?!?!?

There is likely nothing even recoverable in that at all!?!

I did see that 182T with all the corrosion and thought exactly the same thing, someone will likely be very disappointed with it. 

David

[Neomys Sapiens]

mnem
*Whistles gleefully while TASER shopping*

Not that I have a daughter in the critical age band (adopted one is married happily), but I'm working on the integration of stun gun and sjamboek. Might totally improve professional communication with the SW department, contractors, sales reps and so on.

[nixiefreqq]

just a view of the ps and how it mounts should do it for me. am curious to see how similar it is to the one in the 545xx scopes.


and before I get too much flack.  maybe it is possible to restore emission in a crt, but what a crapshoot.  sometimes they kill the crt instantly, sometimes they restore the brightness temporarily, and occasionally it seemed to fix it long term.  maybe some guys know the magic incantation.  but a lot of the time the guy would keep saying "look how much better it is" until he convinced ya' maybe it really was better.

As you can see i already have it out and apart but as i'm sure you can also see there are two connectors and a pair of rails it slides in/out on. They mounted the floppy on top of it as well, real pain in the neck to get at.


New rule, if anyone wants a picture of ANY of my hamfest stuff in detail just ask... too much to take pictures of otherwise.

thanks!  sure hope you did not do all that teardown just for me? 

can see from the pn that the smps is the  same one used in the 545xxa scopes.  did not see the big plastic pins in your picture.  have never pulled them without taking 15 minutes to remember where I set the damn things down.

my 54502a went tits up recently and the problem was leakage from 2 or 3 of those 8 caps stuck between those finned vertical heat sinks. impossible to see they were leaking until removed.

nmen gave me a link to a hand drawn schematic for that smps that really helped a lot.

good luck, and may the force be with you.

[nixiefreqq]

Comparative analysis is a valid troubleshooting technique; one I've been guilty of more than a few times. As long as substitution doesn't become your only repair method, there's no shame in using it as a diagnostic tool.

Just because I'm capable of component-level repair doesn't make me feel obligated to do it that way every time; my time IS worth something, after all. If I can buy a working XYZ board on fleabay for $20, how much diag time can I afford to spend on the original? Sure... figuring out the fault to repair and stow the original board for a spare is a good idea... if you have discretionary time; but I have a bin full of such boards from the Plasma Screen years that are little more than donors for heat sink material and Tesla coil projects now.

I'd definitely replace all 4 at once to be sure your rectifier array all have similar forward voltage drop. Or better yet, replace all 4 with a modern high-current rectifier in a TO-3PJ package.

But first, look for the flaky cap that probably caused the failure.

Here's a thread on this power supply; it links to a hand-drawn schematic which I've attached below.

Hope that helps.


mnem
*tzzzt*

http://www.radiocollection.be/images/restaurations_img/HP54503/supplyHP54503.pdf


yep, that's the link to the smps schematic.

[neo]

just a view of the ps and how it mounts should do it for me. am curious to see how similar it is to the one in the 545xx scopes.


and before I get too much flack.  maybe it is possible to restore emission in a crt, but what a crapshoot.  sometimes they kill the crt instantly, sometimes they restore the brightness temporarily, and occasionally it seemed to fix it long term.  maybe some guys know the magic incantation.  but a lot of the time the guy would keep saying "look how much better it is" until he convinced ya' maybe it really was better.

As you can see i already have it out and apart but as i'm sure you can also see there are two connectors and a pair of rails it slides in/out on. They mounted the floppy on top of it as well, real pain in the neck to get at.


New rule, if anyone wants a picture of ANY of my hamfest stuff in detail just ask... too much to take pictures of otherwise.

thanks!  sure hope you did not do all that teardown just for me? 

can see from the pn that the smps is the  same one used in the 545xxa scopes.  did not see the big plastic pins in your picture.  have never pulled them without taking 15 minutes to remember where I set the damn things down.

my 54502a went tits up recently and the problem was leakage from 2 or 3 of those 8 caps stuck between those finned vertical heat sinks. impossible to see they were leaking until removed.

nmen gave me a link to a hand drawn schematic for that smps that really helped a lot.

good luck, and may the force be with you.

No i didn't do the teardown just for you, was gonna do it anyway because i needed the power supply out to change the caps because something went tits up in this thing, though my timing was influenced by your wanting a picture. Yup, two big plastic pins, i set the screws in a small plastic drawer and so i also set them in the same drawer. Suppose i could get that link?

EDIT; Oh, i see you already gave me the link, thanks! Shame that it doesn't seem to work.

[nixiefreqq]

fixed it. try it again.

page 6.  the 5v supply on top.  the one with 4 diodes in parallel and 8 caps in parallel.  those are the bastards.  the leaky ones were all the way in the back where you couldn't see it.

[med6753]

HP report,
8405a, still has intact factory stickers, a26 is a riser card ( ) and there is a wasps nest on the freq range switch. One of the probe tips, channel a, has broken off, it only has two feet and in general the thing is FILTHY.
HP1645B Didn't open due to special screw head, will have to buy screwdriver or find one. Has a copy of its os disc and i've found one probe, except it isn't quite a probe its just a pin header to pin header cable.
How screwed am i on these two?

hey neo.  when you find a T10 torx driver and get the cover off that logic analyzer I would appreciate a picture of the power supply.


just curious that's all.


ps  that hickok is a thing of beauty.  have a buddy with two of them and he swears by 'em.   guess anyone who owns a frickin' 608 boatanchor needs a good tubetester.


pps  not sure however why anyone needs a crt rejuvenator.   always considered them to be snake oil.

Isn't it a CRT tester too? Kind of useful if you restore vintage TV's to find out if the picture tube picture bulb is any good before spending a lot of time/money on it. See some of Shango066 video's on youtube, he sometimes takes one (powered from a inverter & battery) with him to see if they are worth buying/saving or dragging out of abandoned mine waste dumps.

David

edit: Here is a recent-ish video with on picture bulb testing by Shango066;

https://youtu.be/LZvirB89cxU

Yep, the CRT Tester/Rejuvenator can have some value. If I recall the "rejuvenation" process involves stripping the oxides off the cathode resulting in a fresh surface and higher emission. Sometimes it works and sometimes it doesn't. But even the positive results tend to be short lived.

The other method of increasing CRT emission was those little "CRT boosters" which raised the 6.3V filament to higher value. The results were so-so with them too.

[mnementh]

...and before I get too much flack.  maybe it is possible to restore emission in a crt, but what a crapshoot.  sometimes they kill the crt instantly, sometimes they restore the brightness temporarily, and occasionally it seemed to fix it long term.  maybe some guys know the magic incantation.  but a lot of the time the guy would keep saying "look how much better it is" until he convinced ya' maybe it really was better.

Not at all a crapshoot; they do exactly as they claim. Boils away the top layer of the cathode so it emits better again, and you can see real, actual difference right there in the emission current.  I've had a few that couldn't be helped but never ever had one that the thing killed; the only time that's really likely is when doing a "Remove Short" operation, and if you're at that stage, the tube is junk already with at least one dead gun. Grid-cathode shorts are a common occurrence; that IS a permanent repair unless the short was caused by a dingle who gets in there and fiddles with the SCREEN knob to make things brighter as soon as the tech leaves. 

The real crapshoot is for the tech; they might have to eat a trip charge if the customer is a dickwad who calls you out to do a rejuve because their regular tech has told them they've done it once or twice already and it's time for a new CRT. Whenever I had a customer specifically ASK for a rejuve, I made it explicitly clear that they would be paying my trip charge whether or not I was successful. That tended to eliminate the abusers.

Only problem is it's not a permanent fix; it's just a last-ditch to get a little more life out of a worn-out CRT. How much better and how much life depends entirely on the CRT vs usage cycle; I made it VERY clear to the EU that it REALLY IS just THAT, and I never ever had a single complaint that it didn't last long enough. I used to get $65 a pop brightening CRTs for the local video game halls; had some go another 2 years before taking the final dump. Made a big difference paying my way through school the first time around; and guess who they called for the big ticket when a game needed a new one...

No, it's real science. There is some art to the process in that the machine CAN be made to do MORE than it's intended to by an experienced operator who knows how hard you can push a particular tube before it kakks, but pretty much anybody who reads and follows the instructions can gain a lot of useful life on pretty much any CRT that doesn't have an irreparable short or has been rejuved a couple times already.


mnem
*Nuke Life*

[neo]

-snip-

No, it's real science. There is some art to the process in that the machine CAN be made to do MORE than it's intended to by an experienced operator who knows how hard you can push a particular tube before it kakks, but pretty much anybody who reads and follows the instructions can gain a lot of useful life on pretty much any CRT that doesn't have an irreparable short or has been rejuved a couple times already.


mnem
*Nuke Life*

So then, you approve of its purchase for 10 bucks? 

[mnementh]

mnem
*Whistles gleefully while TASER shopping*

Not that I have a daughter in the critical age band (adopted one is married happily), but I'm working on the integration of stun gun and sjamboek. Might totally improve professional communication with the SW department, contractors, sales reps and so on.

We call that a cattle prod. It IS a VERY effective communication and negotiation tool. 

mnem
*tzzzzt*

[bd139]

Just got to my junk hauling session rather early. It’s crawling with kit so far and they haven’t even finished unloading their cars yet. Good sign 

Turning car round so I can get it in the boot.

[med6753]

Just got to my junk hauling session rather early. It’s crawling with kit so far and they haven’t even finished unloading their cars yet. Good sign 

Turning car round so I can get it in the boot.

Pix or we don't believe you. 

[Specmaster]

Just got to my junk hauling session rather early. It’s crawling with kit so far and they haven’t even finished unloading their cars yet. Good sign 

Turning car round so I can get it in the boot.

Oh good, with a bit of luck the rain might hold off as well. Don't forget your in a new car so don't do a NEO or you may have problems fitting it all in. [emoji848]

[bd139]

Pix soon. Got 7603, Heathkit VTVM and RF sig gen so far and haven’t spent £100 yet

[med6753]

Pix soon. Got 7603, Heathkit VTVM and RF sig gen so far and haven’t spent £100 yet

A 7603? Oh goodie! 

[Specmaster]

Pix soon. Got 7603, Heathkit VTVM and RF sig gen so far and haven’t spent £100 yet

Tek 7603? That's nice.

[bd139]

Yep. Nothing else yet other than tuning caps, toroids and enclosures. 

[med6753]

Pix soon. Got 7603, Heathkit VTVM and RF sig gen so far and haven’t spent £100 yet

Tek 7603? That's nice.

This question is....where is he gonna put it with his limited space? It's a fairly big bastard which is why I built the cart.

"You're gonna need a bigger boat!" 

[Specmaster]

Its a good job his car has a wheel at each corner otherwise his back bumper might scraping the ground on the back to London. I think if as heavy as it looks, my car might suffer that fate as it has a big overhang at back

[med6753]

And......what's the SWMBO gonna say when he hauls it into the house. I predict a massive stink eye and a "What the f... is that!"   

[bd139]

Can’t post a damn picture thanks to iOS attaching it as a jpeg and the supported extension is jpg. All done now. It’s raining and the bargains are done. To note the car did go down when I put the scope in. Well not sure if it was that or I grew a couple of inches.

Got some more tuning caps for projects and an interesting enclosure with a switch a couple of pl259’s and a grounding post which will be reused.

[med6753]

The next ham feast local to me is on Oct 28th. Same one I went to last year and the pickings were slim. I may go again and give it another chance. 

[tggzzz]

Its a good job his car has a wheel at each corner otherwise his back bumper might scraping the ground on the back to London. I think if as heavy as it looks, my car might suffer that fate as it has a big overhang at back

Try Ikea furniture and speed bumps; rear overhang isn't necessary.

And judging by https://www.netweather.tv/live-weather/radar it is already raining and 2-10mm/hr may be on the way.

Interesting dilemma: will there be more/fewer buyers and higher/lower prices when it is raining harder?

[tautech]

And......what's the SWMBO gonna say when he hauls it into the house. I predict a massive stink eye and a "What the f... is that!" 

What worries me more is bd will be tempted to ditch the D83's he has in favor of the 7603. It's a bit bigger but not much.