Roger,
Thank you so much for the information. I only hope my conversion will
go as well as yours. I don't know why, but I don't seem to have Orr's
book, but will get it. According to the dimensions you gave it will be
a tight squeeze and likely some of the facings will have to be removed,
but I think she'll go. I'm sure I'll have many questions when the
actual conversion begins. I certainly agree with your idea to get it up
and running the way it was originally intended before making any changes.
Thanks again... 73,
Rick/K5IZ
KC8OPP Roger S. wrote:
Rick,
Here is what I did to bring the RCA to 160/80/40M.
First thing is get a copy of the "Radio Handbook" by
William Orr, W6SAI. This book has all the answers.
I started by bringing the transmitter up on the freq
the radio station used. I cleaned and repaired as
required. I checked all voltages against the book,
swept the audio section and made more repairs. When
it works as advertised by RCA, then you can start to
have fun.
I removed the master osc board and built a box for the
grid input circuit. I used link coupled coils that
are switched in for each band and drive the grids with
a Kenwood TS-520. The same band switch is used to
changed the taps on the final tank coil. The winding
data for the grid coils was borrowed from the 16th
edition of the Radio Handbook. I did install a grid
coil for 20M, but have never tried the transmitter on
20M, wishful thing I guess.
The final tank that RCA installed was completely
removed and I used the "L" coil for my tank. Vac
variable caps were used for Tune and Load. I put the
circuit together on the bench to find the right taps
on the coil. Use a non inductive resistor in place of
the tube that is equal to the calculated plate load
and then a antenna analyzer connected to the output.
This put me in the ball park and just some minor
changes were needed when the tank circuit was
installed in the cabinet.
The cabinet measured 32 inches deep and 34.5 inches
wide when I removed the meters and switches, just
enough room to fit through the doors. I would guess
that in the stripped down mode the cabinet still came
in around 300 pounds or so.
Hope this helps a bit, I will look forward to hearing
your RCA on the air.
Good Luck and 73's
Roger
KC8OPP
