[time-nuts] Re: Best frequency to start for GHz synth ?

[Wes]

A bit more contemporaneous... it's too long a story to relate here, but I 
discovered that the internal speaker, as well as my voice, tapping on the case, 
etc would FM the VCO in the synthesizer in my Elecraft K3 transceiver.  This was 
a birth defect that affected every one of them. They used my radio (never 
figured out why they didn't use one of their own) to come up with a fix that 
entailed bonding a 1/8" thick aluminum stiffener to the circuit card.  This 
found it's way into production and a retrofit kit was offered for others.

Wes  N7WS


On 4/1/2021 11:16 AM, Richard (Rick) Karlquist wrote:
>
>
> On 4/1/2021 10:32 AM, Lux, Jim wrote:
>
>> And for what it's worth DROs have their microphonic problems too. We had a 
>> breadboard deep space transponder and you could demodulate your voice 
>> (poorly) using the spectrum analyzer's FM demod feature. Very cool. 
>> Unimpressive to the folks who wanted to push the technology.  We were
>
> Back around 1970, as LM radio switched from AM to FM, the HP 608
> signal generator was losing market share because it couldn't
> do FM.  Believe it or not, there was actually an Ap Note describing
> how to obtain FM by bolting a 4" loud speaker to the 608 cabinet
> and driving it with an audio signal generator.  Those were the days ...
>
> Rick N6RK