Eico 221 VTVM - issues - Printable Version

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Eico 221 VTVM - issues - Greggshere - 01-22-2019

Good afternoon guys and gals, I have this VTVM that I obtained on eBay a few weeks ago. It looked decent on the outside, but the inside was another story. Not only was the original kit build terrible, someone else decided to make some of their own modifications, like an extra phone jack with a slide switch.
Anyway with some web searchs I found the original construction manual and decided to tear it completely down, check the major components and install new everything else. I used the step by step build instructions and it came together very nicely. 
Ok, so I fired it up through the variac and at least got the tubed and power light to light. But when checking the voltages from the manual they are way high. On the 6SN7 AMPL. Tube it says pins 2 & 5 each should be about 90 volts. Mine are about 250. Pin 3 should be 3-4 volts, mine is 2.5 and pin 6 should be 3-4 volts and mine is 2.5 volts.
I double checked my connections and also the 33k resistor across the C2 filter (15mfd), also the 10k and 20k resistors between the 6X5 power rec and the 6SN7 tube and all are good. I have no idea if the 15 mfd electrolytic is correct value, because it just calls it the C2 filter everywhere in the manual and schematic. It had a 16mfd in it, but I have no idea if it was correct or not, since the whole thing was a mess. Any help would be appreciated. Thank you!

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RE: Eico 221 VTVM - issues - Chas - 01-22-2019

If there are any connections to the chassis via a riveted or even bolted connection, do this: Loosen & refasten nut/bolt connections. For riveted connections use an aggressive liquid flux sparingly on the riveted joint chassis to tab and a 125 watt or better soldering iron with a large copper bolt. Solder that riveted connection. If cleaned, fluxed properly and the iron suggested used solder flow smoothly around the multiple joints.

Be sure serrated washers are used to secure the pots.

Unless there is a wiring error, a short from wire clippings or a solder splash that should get the voltage down.

BTW the manual does not have voltage test points. Obviously the assembly manual does, strange...

https://stevenjohnson.com/manuals/mfiles/eico221.pdf

Oh, use a 10k to 20k ohms/volt analog meter for the measurements unless EICO species a different meter. A DVM does not load the circuit so readings will be deceptively high.

For the caps, take your pick here: http://www.antiqueradios.com/forums/viewtopic.php?f=8&t=242692

YMMV

Chas

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