[hpsdr] Munin works finally

[Berndt Josef Wulf]

G'day Tony,

I've just completed building my amplifier and can confirm your
observation regarding the instability of the bias current. The circuitry
for Munin2 implements temperature compensation using a NTC resistor and
my plan is to modify my amplifier using this circuit.

The heatsink supplied with the kit gets fairly warm when in idle mode,
e.g. PTT enabled with input and output terminated into 50 Ohms, which
makes me think that it may require a cooling fan for normal operation.

This raises the question about Munin's capability of being operated at
100% duty cycle, e.g. PSK31, RTTY etc. for prolonged time? Is anyone
operating Munin in these modes and what is your experience?

I've yet to test my amplifier with RF applied, so I can't comment on
this.

73, Berndt
VK5ABN

[...]
>  
> Further, what I experienced the bias voltage shifts with the
> temperature rise that might result in instability of the power output
> so something temperature compensated bias circuitry if incorporated
> will enhance the efficiency of the circuit.
>  
> Of course, my present worry is C25,C26,C27 
>  
>  
> 73s
> Tony



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