[Milsurplus] RT-68/GRC - the continuing saga

[BSugarberg]

Hello Jim,

1. Get a copy of "Mil Spec Radio Gear" by Mark Francis KI0PF.

2. Quoting from that book:  "The standard transmit deviation is too wide
for use with modern FM ham gear.  BUT there is a quick and dirty fix. Just
put a resistor in series with the mic input.  You can do this inside the
handset switch, or inside the radio itself.  Start with a haywired 5K pot
to determine the value you want, and replace it with a corresponding fixed
resistor.  Make up for the distant station's lower deviation by simply
turning up the volume."

73, Bruce WA8TNC
=================
Falls, Jim wrote:

> I am working thru the main (complete) schematic for the RT-68 and have discovered that the last portion of the schematic on the right is missing. Looks like it tore off in the distant past. Can anyone send me a copy of this portion? JPG/BMP is fine as long as it's readable.
> 
> Still puzzling over the unmodulated carrier reports even though I hear myself on the sidetone and with my 6M HT (Mic would have to be OK because of the sidetone, correct?). Reception is still bad. Can hear myself if use the HT in the shack, but I don't hear anyone else. All I have are AM sig-gens. Any way to use one of them besides whanging on it and creating "mechanical FM"? I suspect the receiver is badly out of alignment.
> 
> Thought just occurred to me: everyone else in the net is using narrow-band FM rigs. Maybe this is the root of the problem? The '68 has -+25 kHz deviation. My HT runs at 2.5 (5 max). Maybe try a shack to shack QSO w/my colleague who has the same gear? I did the initial RX/TX tests in his shack and the '68 looked A-OK.
> 
> Jim Falls
> KG6FWT
> Eureka, CA