EICO 625 Vacuum Tube tester troubleshoot and repair

A quick troubleshooting and repair video of an EICO 625 vacuum tube tester, a basic emission type that i had received for repair, which there was a complaint of no filament voltage produced on the unit.

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[Tysman]

Shouldn't 12ax7 be on 12.6v not 6.3

[jDS-xhzq]

I have the Eico 625 and would like to replace:

miniature bulb (Part#2 /symbol B3 / #42 OVERLOAD)
+
miniature bulb (Part#3 / symbol B4 / NE-51 SHORT IND.)

Someone knows what are the values needed and where I can find these bulbs?

Thanks

[johncunningham]

Nice clean repair Jordan; having the schematic really simplifies the issue and finding it all comes down to dirty controls, "great demonstration"

[erin]

I just finished restoring my EICO 625. There is really not much to do in the way of electronics on the 625. There is only one Capacitor a .01 Uf /600 volts. Most of the resistors are wire wound 1% and 5% tolerances. The switches are rugged. Testing and calibrating is a snap, since most tube testers check all tubes as a diode. Basically it measures the current flow from cathode to plate. The most crucial part of the tester is the Step down power transformer putting out accurate filament taps.

[zm]

Picked up a 625 several months ago and had exactly the same problems -- dirty filament voltage switch and cracked knob.

[erin]

I find it amazing that these EICO 625 Tube Testers are still around and in such rugged shape. When you consider they are from 1963 and in kit form and, being by hobbyists for the most part. Back in the day I never used a Tube Tester as I had a very good supply of known good tubes, while I worked for RCA Service Company, it was one of the unspoken benefits. I even made service calls to family and friends once I fulfilled my daily service call quota. That's right Mr. Reed, you were right all along. God bless the IBEW!

[SDsailor]

Hey shipmate i thought for a minute i was in the high seas with all the camera movement haha,
Very good video very interesting and informative. I was recently was given one of these and i am looking forward to learning how to use it i was also given a box full of valves so once i learn how to use it i will start testing tubes.
Cheers

[AG]

Hey Jordan, thank you for yet another good if you're feeling brave, why not file a flat on the the shaft for the filament voltage selector? It would need to be carefully placed so that when the grub screw tightens, the knob lines up with the voltage scale correctly. But I think it's worth the effort & the repaired knob will have an easier life too. Thank you.

[nor]

Because of its age I would have change out that wax cap, everything else seem to work, I need to order some d oxit, I been reading and talk to a company about it, I have to clean some volume knobs with it on some older radios I am working on,

[nor]

I understand, it just those old caps sitting there kinda of bug me a little, but you are right when it's a customer property, I just no that thing will fail sooner then later, you did a great job on, I hope to see a lot more of your videos

[nor]

So where did you buy that chicken head knob at, I need to replace a channel select knob on a tube radio I am working on, anyone know where I can find some universal knobs at anyone

[socksumi]

I have a Eico 625 I picked up but it has no listed settings for 6CA7 tubes. Anyone know what the settings should be for this tube?

[Tysman]

I would replace resistors should fix those lower voltages