[MRCG] Poor conditions in Eureka

[Mark J. Blair]

> On Sep 7, 2014, at 21:33, Tim <timsamm at gmail.com> wrote:
> 
> Hi Mark - well my CV-2455 filters could be mistuned.  I'll try to figure
> out how to test the tone freqs to see if there is a detectable problem on
> this end.  There's gotta be knobs in there someplace!  On receive, it was
> working fine...  But it IS 50 years old.....

Is real repair documentation available for that converter? I'd want to know what the specs are before turning any pots. 40 Hz might be well within the allowable tolerance range. 

With AFC turned on, Fldigi locked on to your mark tone, and your space tone was just a bit off to the right from the space cursor on the waterfall. Center frequency error was on the order of 10 Hz if I recall correctly, which is a lot smaller than the errors we'll expect to see from sets like the GRC-46 or GRC-26D. The main thing I'm curious about is how tolerant the CV-2455 will be on Rx. The GRC-46/etc. are going to be the hardest of the bunch to keep on Tx frequency without "cheating" with something like an outboard VFO (as I probably will do to be a well-behaved NCS), and the PRC-47+CV-2455 seems like the set with the fewest knobs for chasing off-channel signals around on Rx. 

Well, a big motivation for bothering to do this at all is to learn the operational intricacies that we can't pick up by just reading TMs. Maybe RTTY operators from mechanical VFO days just spent a lot of time tweaking knobs, and we'll learn to do the same? Or maybe the channelized sets were deliberately tolerant of the older sets, and it'll just work? Maybe our modern gear just gives us unrealistic expectations of how perfect things must be to get traffic through? I'm having a lot of fun learning about this stuff.