> Interesting. I just did the same test using my TS-930 with 400 Hz
> filter and my unmodified Mark 5. At 500 Hz from the carrier
> frequency, clicks were down to below S3 from 59 +20. Acknowledging up
> front the apples-and-oranges nature of the two test setups, this seems
> to suggest that the stock Mark 5 may not be as bad, click-wise -- in
> fact, that it is in the same ballpark as a modified MP. Does this
> track with others' (hopefully better) data?
Hi Pete,
According to my notes, I've received a total 23 e-mails from MKV
owners asking for a click mod (prior to this topic coming up). Three
MK V owners said others constantly complain about their signals.
One owner has stopped using his rig on CW. The people with the
most complaints seem to have the strongest signals, and live in
the most congested areas.
One thing that can cause us to see different S meter results
(although the QRM results will be the same) is non-linearity and
response times in the AGC system, as well as group delay in
filters that may affect transient response. Filters can weaken and
"stretch" the energy in a pulse. Remember the click you are trying
to measure is only a millisecond long or less, so you should use
slow AGC and hopefully the transceiver will have a good response
time in the AGC!
Also Pete, check up and down about a kHz or two. See if the
clicks peak. The FT1000D has a strong click peak at the pole
frequency spacing of the SSB filter, because the square keying
waveform reaching the filter rings the "poles" of the filter.
While over the air measurements are possible, if anyone lives in
the Macon/Atlanta area and has a MK V and wants to bring it to
my QTH (30 miles NW of Macon a few miles off I-75), we can
compare it to other radios.
73, Tom W8JI
W8JI@contesting.com
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