[Milsurplus] BC-610 India RY 5 over current relay trips when mic unkeyed or heavy modulation

[Mack McCormick]

Friends,

I could use some advice please. I have a BC-610I that has performed
flawlessly at least one a week for over 15 years.

Just recently RY5, the over current relay, began tripping when I unkeyed
the transmitter. I'd appreciate any suggestions on why this may be
occurring and how to prevent it from tripping when I unkey. Has the relay
become defective? I didn't see any adjustment procedure in the manual like
there is on my T-368.

Here are some facts. Plate current is 205ma. I see/hear no signs of arcing
on any high voltage wiring. I have replaced the 3B28's, 150th's and 250th
all with NOS tubes. If I push the modulation level a bit on the BC-214
speech amp the HV relay will also trip. I know the normal trip point of
this relay is 670 to 710ma.

Does anyone have a replacement RY5 from a parts rig? Have a suggested
circuit to replace it with a modern DPDT relay (I'm thinking of a resistor
in parallel with the relay coil that would pull the coil in when 700ma is
pulled through it). Could the spark gap on the bottom of the 11H filter
choke be arcing during unkeying?

73,

Mack
W4AX
https://www.qrz.com/db/w4ax
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