[CQ-Contest] Key Clicks

Jim Brown k9yc at audiosystemsgroup.com
Fri Jun 5 13:47:52 EDT 2020

On 6/4/2020 9:05 PM, Igor Sokolov wrote:
> It must be conveyed to participants in contests that 6 ms is the minimum.

The slides for this talk by K6XX and me to NCCC includes a series of 
waterfalls and spectra from a neighbor's ICOM rig as the setting is 
varied from 2-10 msec.


On 6/4/2020 7:32 PM, Joe wrote:
 > What do Key clicks look like in these new rigs waterfalls?
 > Maybe take screen shots?

I posted links yesterday.


On 6/5/2020 7:12 AM, Kimo Chun wrote:
 > I'm fairly sure all FT1000mp's (original) manufactured up to middle 
to late
 > 2004 have this problem (per Inrad).

The defect in Yaesu radios persisted through at least three model upgrades.

We were reminded of this, recently,
 > when one of our spare radios at the M/M was reported to be doing this. We
 > had failed to ensure all the radios had been modified years ago.

Neighbor K6XX encountered this when he bought a used MP and used it in a 
contest. We had a conversation the next day, and he modified it. Months 
earlier, soon after I had moved in 3-4 miles down the road from him, he 
called me about clicks. In a few minutes, we tracked it down to a noise 
cancelling unit, in which the carrier detection circuit was causing the 

On 6/5/2020 8:22 AM, robert wa1fcn wrote:
 > Other than sending radio out for a modification, does anyone know menu
 > settings for a FT 1000mp Mark 5
 >              that can help or at least lesson  key clicks ?

No, there are no menu settings in those radios that can fix their 
clicks. The hardware mod from Inrad or using W8JI's advice is required.

On 6/5/2020 5:51 AM, S57AD wrote:
 > Occasionally I warned some guys the have bad clicks. In most cases they
 > retort "I use first class radio, the fault is on your receiver." So I 
 > radios (especially first class ones9 should be addresses for having bad
 > clicks.

Point them to these links, which clearly show the problem.


I had the same problem with a different neighbor, a lawyer with no 
technical background, who went legalistic on me. He had an Icom 7600 
that was burning 10-15 kHz of whatever band he was using. He said the 
rig passed FCC type-acceptance limits, and he was going to use it. (He 
failed to read the next paragraph that said a signal could occupy no 
more than the minimum bandwidth required for the communications type 
being employed.) 5 years later he bought a K3S, and maybe also a Flex 
6000-series rig, so his signal is now clean.

When the K3 came out in 2008, my neighbor W6DRX (about 700m distant) and 
I both bought them to replace existing rigs because, as engineers, we 
knew it was the only way that we could co-exist. I was running a pair of 
(fixed) MPs at the time.

When I was growing up, we were taught that with rights we also had 
responsibilities. In ham radio, we are licensed for high power and can 
build big stations. With that comes the responsibility to transmit a 
clean signal that burns no more bandwidth than required.

73, Jim K9YC

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