[Skimmertalk] RP-16 front end tenderness

[Bob Wilson, N6TV]

On Thu, Jul 11, 2019 at 4:48 PM Jeffrey Pawlan <jpawlan at pawlan.com> wrote:

> The version 1 schematic that Bob sent me says +/-  1v max.
>

It also says input impedance (Rin) is 1 Meg Ohm, which is copied from the
old RP schematic, and clearly no longer applies.

However if that 1:4 transformer is stepping up the RF voltage by a factor
for 4, and the ADC chip can't handle more than 4V RF input, them maybe the
1V number is correct.  What's typical for a 16 bit ADC sampling RF?

The old RP-14 schematic said 30V max, but that was in it's factory
configuration with large input resistors, not a radio with the impedance
pad bypassed.  It then says 30 ma Max on the amplifier and filter, no
longer present in the RP-16 schematic.

I was trying to evaluate the ratings of all the components in the input
chain, one by one, as I have already done for the transformers.  1V seems
quite low for those.

73,
Bob, N6TV
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