Dirty power supply connections can happen to every user. Perhaps a
regular cleaning interval is indicated, something like every year or
two. Accompanied by a drop of DeoxIT on the contact surfaces to clean
and delay the need for future cleaning.
Chirp from the voltage change at key closure might hint at a need for
better voltage regulation of some oscillator, perhaps with a voltage
regulator chip needing less head room than the LM34x or 78x families.
Though that much voltage drop probably also leads to a serious loss in
output power.
73, Jerry, K0CQ
On 5/14/2010 1:43 PM, dtx@verizon.net wrote:
> I have occasionally had a chirp report from my 0-IV, invariably caused
> by a dirty power supply connector and cured by a proper cleaning. The
> scope pattern of its keying has been decent from the start - did take
> the time a few years ago to measure the rise and fall times - forget the
> numbers but since were in the range of above too sharp and below too
> soft at 35 wpm didn't bother to record. K3TX.
>
> On May 14, 2010, *Dr. Gerald N. Johnson* <geraldj@weather.net> wrote:
>
> There are also complaints of a chirp from the Omni VI. Typically heard
> only by other Omni VI users. It is a fact that the BFO crystal is
> shifted at key closure from receive to transmit. So it is heard at the
> other end of the connection and passes through the SSB filter. I
> suspect
> the "click" and chirp are increased by the phase response at the
> edge of
> the filter pass band and increased more by the edge of the filter pass
> band in the receiver that's detecting the signal. I know I've listened
> to a supposed clicky and chirpy transmitter (Omni VI at W1AW on 20
> meters) and found no hints of either click or chirp using a tentec or
> other receiver even when I tuned to a very low pitch which makes chirps
> more pronounced.
>
> This topic has not been on this forum for a year or two, maybe three.
> But there should be extensive discussions in the archives.
>
> Fact is, you need a rapid rise which leads to a hard signal when you
> run
> CW above 15 wpm, faster if you run 40 or 50 wpm. Else the bits of
> characters run together and get hard to copy. That also happens with
> narrow CW filters from other vendors, it was noticable with a 400 Hz
> filter in a Kenwood at speeds of only 25 to 30 wpm.
>
> There are thousands and thousands of happy Omni VI CW operators happily
> working rag chews, traffic, and DX without click or chirp complaints. I
> don't have one simply because I prefer USB for CW, especially on VHF
> with a transverter where USB is the standard voice mode and mixed mode
> contacts are common.
>
> 73, Jerry, K0CQ
>
> On 5/14/2010 8:29 AM, Roger Rippy wrote:
> > "As you may know, most TT rigs up to the Orion series, have
> fairly hard keying, and we have occasionally got comments about
> "sounds a bit clicky".
> >
> > What is the consensus of the Omni VI operators? Do you routinely
> receive these comments from others? I have not received a comment
> about hard keying or clicking from my Triton IV, but then it is
> quite a bit older than the Omni VI.
> >
> > Just curious since I am considering buying an Omni. Thanks, Rip
> > Roger Rippy W7RIP Bozeman, Montana
> >
> >
> >
> >
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> >
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