[Boatanchors] AGC Modded NC-183?

[Philip Atchley]

Hi All,

Saturday a couple 'new' radios found their way to my shack (a nice National
NC-183 and a Yaesu Frog-7).

The National is going through an ENTIRE recap and overhaul prior to it's
even being plugged in.  The radio has obviously had a moderate amount of
work performed in the past, and for the most part it was done fairly well (A
'few' component replacements COULD have been a little neater).  At least it
isn't full of holes and a bunch of OBVIOUS mods.  It seems to have had at
least a PARTIAL recap sometime in it's past as the paper capacitors are
about 50 percent wax coated cardboard by Aerovox and 50 percent the
(somewhat) newer PINK plastic ones by Sangamo.  It is fairly obvious the
pink ones were replacements (and getting replaced again).

HOWEVER, there is one section in the RF area that has obviously been modded.
The first RF amplifier tube (6SG7) has been removed from the AGC/RF gain
control chain and tied directly to ground so that stage has only the bias of
a 68 Ohm Cathode resistor.  I can understand the 'why' of this mod.  With
the first RF amplifier running wide open it 'probably' gives a better
S/Noise radio on weaker signals that just "start" to activate the AGC. BUT,
it might also lead to front end overloading on strong stations.

QUESTION:  Should I leave the radio set up this way OR go back to the
original circuit?

73 de Phil,  KO6BB
DX begins at the noise floor!

THE BEACONEER'S LAIR:   http://www.geocities.com/ko6bb/
MY RADIO-LOGS:       http://www.geocities.com/ko6bb/Logs/
QSL GALLERY: http://photobucket.com/albums/f306/KO6BB/
Merced, Central California,    37.3N  120.48W  CM97sh