I was reviewing the assembling of this tester and came upon this problem. The instruction are to connect a green wire from R16-2 to S28-7 I noticed that there was another part added to this connection which was a #47 bulb.
The green wire still gets connected to S28-7


[Upon further investigation I also found out that part #R16 Grid wiper was damaged



Is the bulb their to replace the grid wiper.?

Gerry

A quick look at the schematic (available on bama link below) would seem to indicate that someone installed the bulb to bypass the damaged grid potentiometer R16. I doubt it works very well. You should start looking for the proper replacement for R16. Also, find out why it got damaged, although it's possible that a severely damaged tube was the culprit. Has the unit had it's capacitors replaced?

http://bama.edebris.com/manuals/eico/666/

This was a fix to protect the pot if you tried to test a shorted tube or used the incorrect setup. It would limit the current to the pot. Looks like it was installed to late.

Dave

I have a 5K, 4W pot in the same style. It's about 1.5" in diameter and 5/8" thick. Shaft is 1/4" diameter and about 5/8" long (cut off in the past) but this one does not have a switch.
Etching on back is 10603 / 5M / 4 Watts / #25 / 4109
It has been used in the past but is operational. There is some solder on tabs which indicates it's been used.
I don't know if your switch would attach to the pot or not nor do I know if it would work if attached. I have not opened the housing. Does this sound like anything you may be interested in using?

Barry
I replaced all the caps and resistors that were out of tolerance.

Dave
After reading your post I searched the forum and there was a good write up on why and how to install this part . I think you were correct in saying it must have been done after the damaged was done.


Bugman
I am no sure on how to proceed to make the fix but I will keep you in mind.

Thanks
Gerry

Gerry,
I think the only way you can proceed is to replace the control.Someone on this site posted a part number from Digikey that works well as a replacement.I had saved the link to it on my other computer because I have an Eico 667 that uses the same control and I THOUGHT there was a problem with it.

Unfortunately,that computer died so I can't retrieve that information for you,but you could search Digikey's site.

That control may have burnt windings,but I can tell you it was also damaged when someone removed the cover and was a little too wild with their prying tool.

Edit:Found the part.The thread was on another site:https://www.digikey.com/products/en?mpart=026TB32R502B1B1&v=119

Mike

I looked up the part and seen that it's only the switch. My question is how do you connect S29 to it.

The two photos show the top and bottom of this part. How and were do I make the connection to make this one unit.?

Has anyone ever done this.?

I'm not certain I understand the question. The ORIGINAL part was a combination of wirewound potentiometer and switch. The switch part is attached to the rear cover as you see, and activated by the cam on the shaft of the potentiometer. Putting them back together wrong will further damage both.

You might be able to find a modern replacement part that will work properly, but you need to know the value and wattage of the original pot, make sure it will mount properly and the shaft is correct for your knob, and that it has a switch configured the same as the one on the original. Otherwise you'll have to do some clever "manufacturing" to get this replaced, or find one online that is an exact replacement.

Try Mark Oppat at oldradiopartsDOTnet/ he should be able to help you.

Dave

Barry
I was just wondering how to make the connection for the new switch to S29.

Dave
I think I will contact Mark to see if he has the part I need.

Gerry

I don't know what to tell you guy,the description reads 5k linear wirewound potentiometer with spst switch.

"POT 5K OHM 5W WIREWOUND LINEAR" "Built in switch-rotary,spst"

Mike

This will teach me to read the whole description of the part.

Gerry

No sweat man,hope you get your tester up and running.