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Bitrex

On 11/22/2017 09:54 AM, wrote:
What is your wallplate voltage?

110:195 = XXX/260 where XXX = 147 VAC.
110:210 = XXX/275 where XXX = 144 VAC.
110:3 = XXX/4.8 where XXX = 179 VAC

These results are reasonably self-consistent as what comes to a volume-control can have many variations. Note that increasing capacitance in many cases will also increase B+ and other down-line voltages, and generally *SHOULD NOT BE DONE*, especially in radios with field-coil speakers such as that one.

Using my DMM on the "AC" setting, out of the wall it's reading 124 VAC.

So, hazarding a guess at long distance, you have a combination of high wallplate voltage, excessive capacitance and measurement variance.

This voltage of 14X seems extreme, but given that these sets were measured with VTVMs back in the day, and VTVMs load very differently than a modern VOM. And the vintage unit was not "true RMS" and so could measure low. Do you have an old analog meter? Or, perhaps a VTVM?

I have long-since learned to distrust factory-schematic voltages. Generally. I will bring a radio up to 110V on the Variac and measure secondary voltages off the transformer (unloaded, then loaded) to see what is what. If I get consistent discrepancies, I attribute it to measurement variances. If I get inconsistent discrepancies - more than 15% apart - I will look for a bad transformer winding or some other problem of that nature.

Did you replace the line-filter cap on the line-cord? Do so with a type Y safety capacitor. That will help on reception.

I have no idea where you are, but if you are anywhere near southeastern PA, USA, I would be glad to test your tubes. I keep both a little Simpson emissions tester and a Hickok 539B for the heavy-duty stuff.

Thanks for the offer! I'm currently in Providence, RI most of the time
so a little far, unfortunately...

Otherwise, try swapping tubes with another radio. 6A8s are notoriously prone to failure, and glass ones are getting quite scarce. More so than even a 1L6 in my experience.

Peter Wieck
Melrose Park, PA

Will do. Yeah, gosh, NOS 6A8Gs are expensive! The schematic specifies
either the metal or "G" shape enclosure, I guess the GT doesn't have the
correct pinout? In any case, all the tubes currently fitted in the set
are the metal enclosure type.