RM 203P Constant Chatter/Clicking

[OldModel]

Trying to add some 10-meter help, to my old TenTec 509 QRP rig. An extra 50 watts or so can help finish a QSO sometimes. 1 watt input, and clicking, when mic is keyed with amp on. Clicking stops once modulation is started. Slower clicks in SSB and then, rapid fire clicks on AM when mic is keyed. Suspect relays are not happy for some reason? Any one run across this before? Radio is fine with no amp.

 

[pienari]

Hi.
Is the 1w output deadkey power am?.
i think amp maybe need more input power.
If full power can be reach at 4w dk at am/fm.

 

[OldModel]

Yep 1 watt on dead key, AM. Once you speak into the microphone, clicks stop and power out from the amp. Upped the power to 2 -1/2 watts and no difference. Installed the amp on 2 other rigs and no clicking and full output from amp with 2 watts dead key from both radios. I suspect maybe issues with the 1/4-inch mic plug wiring into the amp from Ten Tec 509, is affecting voltage to relays.

 

[doffo]

Only time I had problems with the relay clicking oddly is when the coax going from the radio to the amp was longer than 3 feet? From what I understand its best to keep that run of wire as short as possible between the amp and the radio. Also what didnt help is that my antenna's coax cable on the outside of the house had a bad end from the beginning, so had to solder in a new end. After that, the antenna works awesome.

 

[OldModel]

Only time I had problems with the relay clicking oddly is when the coax going from the radio to the amp was longer than 3 feet? From what I understand its best to keep that run of wire as short as possible between the amp and the radio. Also what didnt help is that my antenna's coax cable on the outside of the house had a bad end from the beginning, so had to solder in a new end. After that, the antenna works awesome.

Yep! I have been down that road in the past.

 

[BC Coyote]

From what I understand its best to keep that run of wire as short as possible between the amp and the radio.

That's true ! Furthermore, ALL coax interconnect cables should all be as short as possible.
This stuff you constantly hear about needing all cables to be 3 feet or 8 feet or 16 feet or whatever is the single biggest bunch of snake oil in the CB hobby. If everything is done right with the antenna (including having a proper balun), and the radio is installed properly and hasn't been golden-screwdrivered (also known as peak and tune), and the amp is biased properly and has an LPF behind it, then the length of cable shouldn't and doesn't matter.
This might be hard to attain in a mobile setup where every antenna is a compromise antenna, but it's not so hard to do it on a base station setup.

The reality is that if changing the length of a cable changes the SWR or changes the signal strength or makes the amp chatter or stop chattering or whatever, then there is something wrong somewhere, and fiddling with cable length to make it happy is only putting a band-aid on the problem rather than addressing the actual root cause.

Of course, in the world of CB radio we deal with a lot of compromise antennas, tweaked radios, unfiltered amps, and all the rest of it, so it's not too surprising that so many people DO have to mess with the length of their cables.

 

[doffo]

That's true ! Furthermore, ALL coax interconnect cables should all be as short as possible.
This stuff you constantly hear about needing all cables to be 3 feet or 8 feet or 16 feet or whatever is the single biggest bunch of snake oil in the CB hobby. If everything is done right with the antenna (including having a proper balun), and the radio is installed properly and hasn't been golden-screwdrivered (also known as peak and tune), and the amp is biased properly and has an LPF behind it, then the length of cable shouldn't and doesn't matter.
This might be hard to attain in a mobile setup where every antenna is a compromise antenna, but it's not so hard to do it on a base station setup.

The reality is that if changing the length of a cable changes the SWR or changes the signal strength or makes the amp chatter or stop chattering or whatever, then there is something wrong somewhere, and fiddling with cable length to make it happy is only putting a band-aid on the problem rather than addressing the actual root cause.

Of course, in the world of CB radio we deal with a lot of compromise antennas, tweaked radios, unfiltered amps, and all the rest of it, so it's not too surprising that so many people DO have to mess with the length of their cables.

That explains why the amp was struggling when all along the other end of the coax up the antenna was the problem all along.

Also, I think someone was calling it "nulling" the coax cable or something where you had to run it at certain feet? I forget what all that was, but he swore by it and needed to be done lol. I didn't buy into it, but only told him that if the length of coax is somehow magically fixing the SWR, then there is a problem somewhere else. Much like you mentioned.

 

[9C1Driver]

Yep 1 watt on dead key, AM. Once you speak into the microphone, clicks stop and power out from the amp. Upped the power to 2 -1/2 watts and no difference. Installed the amp on 2 other rigs and no clicking and full output from amp with 2 watts dead key from both radios. I suspect maybe issues with the 1/4-inch mic plug wiring into the amp from Ten Tec 509, is affecting voltage to relays.

This has me very confused. Why would you run a mic plug into the amp? As far as jumpers, I have used 3 and 6 foot jumpers on every amp I have ever had with no problems. Here is a nice article on the KL203.

RM Italy KL203P CB Amplifier | CB Radio Magazine

RM KL203-P Amplifier Review The KL203 has been one of those amplifiers I recommend to people again and again over the years. They are inexpensive, they put out a solid 100 watts, which is more than enough for most DX, and as long as you don’t overdrive them they can last for quite a RM KL203-P...

cbradiomagazine.com

 

[OldModel]

This has me very confused. Why would you run a mic plug into the amp? As far as jumpers, I have used 3 and 6 foot jumpers on every amp I have ever had with no problems. Here is a nice article on the KL203.

RM Italy KL203P CB Amplifier | CB Radio Magazine

RM KL203-P Amplifier Review The KL203 has been one of those amplifiers I recommend to people again and again over the years. They are inexpensive, they put out a solid 100 watts, which is more than enough for most DX, and as long as you don’t overdrive them they can last for quite a RM KL203-P...

cbradiomagazine.com

 

[OldModel]

Mic plug is going to radio. Not the amp.

 

[linearone]

That explains why the amp was struggling when all along the other end of the coax up the antenna was the problem all along.

Also, I think someone was calling it "nulling" the coax cable or something where you had to run it at certain feet? I forget what all that was, but he swore by it and needed to be done lol. I didn't buy into it, but only told him that if the length of coax is somehow magically fixing the SWR, then there is a problem somewhere else. Much like you mentioned.

I mean, thats kind of loaded statement dont you think? The difference in measurement is easily seen with different length coaxes, especially if they are at weird multiples. Especially if you are looking into, say , the input tuning network of an amplifier. Im not saying youre wrong, but you are half right.

I always think about that famously attributable quote that Mike Tyson had, " everyone's got a plan until they get punched in the face".
Everybody's plan is to run whatever oddball coax jumpers they have between everything and then hope everything's okay, a lot of the times it is. Sometimes you have a weird issue that you can't resolve without putting in jumpers that are cut to a null.

 

[linearone]

I mean, thats kind of loaded statement dont you think? The difference in measurement is easily seen with different length coaxes, especially if they are at weird multiples. Especially if you are looking into, say , the input tuning network of an amplifier. Im not saying youre wrong, but you are half right.

I always think about that famously attributable quote that Mike Tyson had, " everyone's got a plan until they get punched in the face".
Everybody's plan is to run whatever oddball coax jumpers they have between everything and then hope everything's okay, a lot of the times it is. Sometimes you have a weird issue that you can't resolve without putting in jumpers that are cut to a null.

And just to be clear I'm not saying that any coax length fixes your SWR.

 

[doffo]

And just to be clear I'm not saying that any coax length fixes your SWR.

I am sure I worded it wrong. I just meant like I kept masking the real problem without me knowing what the real cause was by changing the length of the coax between the amp and the radio. In the end, it turned out to be end on the antenna outside. It wasn't water related, but the end they used for the coax was really bad. Its been good since I replaced it for a new connector end.

 

[9C1Driver]

Mic plug is going to radio. Not the amp.

Ok well I’m glad you clarified that because he clearly stated just the opposite which made no sense.