[ARC5] Starting on a RAL clone

[Bill Cromwell]

Hi,

I haven't had any success finding a RAL at any of the hamfests. I don't
get to very many of those. My funds for a RAL are limited and the
shipping cost for a distant RAL added to the three digit asking prices
puts those out of reach and there are very few of those, too. While I am
waiting to find a real RAL to pair with my RAK I am going to start
construction on a RAL "clone". I'm not looking to "miniaturize" it nor
make any "improvements". I am considering how I can use available
materials to copy the function of the RAL. That will probably make my
"clone somewhat smaller but not a mini by any means. I have noticed the
manuals i got from BAMA contain detailed info about al the tuning
inductors, etc. Mission critical info there.

I will be using miniature tubes. Think 6BA6 or something like that. I
have them by the dozens. To help with the decision about which tubes to
use I'll compare their characteristics to the 6D6 and 41 tubes used in
the RAL. There won't be any with grid caps. There will be shields even
though they may not be needed with the grid lead not already exposed to
the plate.

I have been considering how I can mechanically implement a tuning
mechanism that duplicates the presentation and operation of the one used
in the RAK/RAL. I think I can acquire the needed gears to put one
together. Not an exact duplicate but the same dual dial layout and same
number of revolutions. There may be something easier to implement. My
RAL clone will NOT be going into Naval combat any time soon! Some
combination of cords, belts, chains, and drums may be reliable for home
use.

There is a lot of shielding and isolation in those radios. I intend to
pay close attention to all of that and incorporate it into my "clone".
The tuning mechanism, volume of shielding, and size of audio inductors
will need some space but even so, the "clone" is likely to be a little
smaller than the real deal. I'll be building on either two or three
separate chassis inside the cabinet...not counting the power supply.

Anybody have suggestions or known 'gotchas" to pass along? Resale value
is NOT a factor. I'm only making one and it's for me to use until
burial. The radio can be buried too.

73,

Bill  KU8H