[Moon-net] IC746 transient output spikes

[Dave Blaschke]

Lance

Here is my solution to all these types of problems:

TX ON sequence:
1. Antenna relay(s) + preamp protection
2. AMP  (+ brick, if used)
3. Transverter  (if used)
4. Transceiver TX out

TX OFF sequence (back to RX:
1. Transceiver RX in
2. Transverter (if used)
3. AMP (+brick, if used)
4. Antenna relay(s) + preamp protection

The ARR 1-2-3-4 sequencer works nicely for this. I have it timed to 
take about one second to step through all four. More than enough time 
for relay switch bounce setteling. If I am running JT65, I let the 
computer comm port DTR/RTS trigger the sequencer.

If I am running CW, I use a manual switch to trigger the sequencer 
(unless I am using a CW program, like CWkey5. Then I let the computer 
comm port DTR/RTS line trigger the sequencer, just like it does with WSJT.
The only caveat is NEVER RUN THE RADIO in break-in or VOX mode, so 
that pressing the key cannot cause TX.


Dave, W5UN
At 20:41 3/7/2008, you wrote:

>A bit off topic, perhaps, but I know others here also have these rigs.
>
>I have an IC746, and have been pleased with it so far.  However, I 
>often see RF
>power output spikes when I switch to XMIT. This is more of a concern 
>now, because
>I am planning to use this with a solid state amp which cannot 
>tolerate any such
>excessive power input spikes.  Is there some work-around for this 
>problem that I
>can implement here?  I look forward to any suggestions you might be 
>able to provide.
>
>Thanks and 73, Lance
>--
>Lance Collister, W7GJ (ex: WN3GPL, WA3GPL, WA1JXN, WA1JXN/C6A, ZF2OC/ZF8)
>P.O. Box 73
>Frenchtown, MT  59834  USA
>QTH: DN27UB
>TEL: (406) 626-5728   URL: http://www.bigskyspaces.com/w7gj
>2m DXCC #11, 6m DXCC #815
>
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