Re: LF: Receiver protection

[N1BUG <paul@n1bug.com>]

Hi Chris,

It is good to hear you are making such progress with the TS-590.
Good job.

Apparently my system doesn't need fancy receiver protection. The
Softrock was a lucky choice in this respect. :) Now I see why it
survived last winter! I kept expecting disaster every night.

However I am still curious about the U3S TX delay timing and will
try to do some checks on it when I finish a few projects now on the
bench. I don't mean to speak ill of this fine unit, without which we
would be in a much harder place with beaconing, and we would not
have had our QSO. However in fairness there are a number of features
that don't work quite right and some that don't always work quite
right. It wouldn't surprise me to see occasional anomalies with the
TX delay timing. It will be very difficult to know for sure, as
there are nearly infinite possibilities of settings and modes which
might alter its behavior. Also I believe you are running later
firmware than mine, which may change the picture. That's another
'risk' with updating firmware on anything. While it may fix known
issues, it can also introduce new ones. This is just a fact of life
with firmware updates on anything.

73,
Paul N1BUG


On 07/11/2018 08:55 AM, Chris Wilson wrote:
> 
> 
> Hello N1BUG,
>  Hi Paul,
> 
>  As I am deeply entrenched in mending my TS-590 after a whoopsie put a
> load  of  137kHz  RF  up its RX antenna socket I am very interested in
> proection  measures  too!  But  even more so I am interested in if you
> find any anomalies with the U3S TX delay timing as a detailed check of
> my  antenna  switching box shows no issues at all. But if the U3S had a
> switching / timing glitch that may be another matter. Can anyone think
> of  a way to long term record the timing of the switching voltage from
> the  U3S?  I had a long delay 500 milliseconds plus, which should have
> been  plenty.  I  have  a  USB scope with what they call a "Roll Mode"
> option, but i don't recall ever using it.
> 
> The 590 may, very surprisingly, live again, I have replaced some ultra
> tiny  PIN  diodes, three ceramic caps, some input overload diodes, and
> an  inductor.  I  now  have TX and receive on all but three "bands"
> These  seem dead due to the BPF switching digital transistors on those
> bands  having  high resistance collector resistors, up from 68 Ohms to
> around 7k. I have ordered some new ones and as the digital transistors
> are  all  switching  state  ok,  the BPF's themselves seem OK, and the
> shift  register IC's are working I may be getting to a conclusion with
> it. They don't like it up `em as they say :)