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RF output when just keying the mike

Maurice Bersan
 

Hi everyone looks like I have problem.
I have RF output of about 5w when I key the mike with no modulation input. When I do speak into the mike the modulation is very distorted as heard on a local SDR.
CW seems fine with a nice clean signal.
The problem happened suddenly while trying to tune up with a manual antenna tuner.
I replaced the two irf510 fets but no change. Anyone have any ideas where I can start looking?
Thanks for any help
Maurice
Vk6hly

Maurice Bersan
 

Sorry forgot to mention it's ubitx v5

 

Check you BFO. If that is fine then it my be a mixer diodes D5.

Raj

At 06/11/2019, you wrote:
Hi everyone looks like I have problem.
I have RF output of about 5w when I key the mike with no modulation input. When I do speak into the mike the modulation is very distorted as heard on a local SDR.
CW seems fine with a nice clean signal.
The problem happened suddenly while trying to tune up with a manual antenna tuner.
I replaced the two irf510 fets but no change. Anyone have any ideas where I can start looking?
Thanks for any help
Maurice
Vk6hly

iz oos
 

I in my opinion the carrier is within the passband, you should move the BFO to have a crystal clear modulation.


Il 06/nov/2019 08:27, "Maurice Bersan via Groups.Io" <Vk6hly=yahoo.com@groups.io> ha scritto:
Hi everyone looks like I have problem.
I have RF output of about 5w when I key the mike with no modulation input. When I do speak into the mike the modulation is very distorted as heard on a local SDR.
CW seems fine with a nice clean signal.
The problem happened suddenly while trying to tune up with a manual antenna tuner.
I replaced the two irf510 fets but no change. Anyone have any ideas where I can start looking?
Thanks for any help
Maurice
Vk6hly

Maurice Bersan
 

Thanks the help so far, yes it is a calibration/bfo settings issue. I still struggle to set them correctly. So I'm using factory default settings at the moment, works ok but sounds like it has to much trebble. 
Cheers
Maurice
Vk6hly

vk6qa
 

Hi Maurice

Is your radio receiving ok and have good sensitivity?

Have you tried it on several frequencies i.e. 3 .5 mhz, 7.10mhz and 14.1 mhz? for both RX and TX?

 

Keith Perry

 

 

 

From: BITX20@groups.io [mailto:BITX20@groups.io] On Behalf Of Maurice Bersan via Groups.Io
Sent: Wednesday, November 6, 2019 3:27 PM
To: BITX20@groups.io
Subject: [BITX20] RF output when just keying the mike

 

Hi everyone looks like I have problem.
I have RF output of about 5w when I key the mike with no modulation input. When I do speak into the mike the modulation is very distorted as heard on a local SDR.
CW seems fine with a nice clean signal.
The problem happened suddenly while trying to tune up with a manual antenna tuner.
I replaced the two irf510 fets but no change. Anyone have any ideas where I can start looking?
Thanks for any help
Maurice
Vk6hly

Maurice Bersan
 

G'day Terry, yes receives fine however does not transmit on 6793 which is a commercial frequency I occasionally use. I haven't looked into that one yet but no problems on any of the ham bands.
I find if I zero beat during calibration to a local am radio station that's when the problem with Ptt occures, so I must be doing something wrong there.
Cheers
Maurice

 

Set it to 11.0555 and see if it sounds fine and no carrier leak!

Raj

At 06/11/2019, you wrote:
Thanks the help so far, yes it is a calibration/bfo settings issue. I still struggle to set them correctly. So I'm using factory default settings at the moment, works ok but sounds like it has to much trebble.
Cheers
Maurice
Vk6hly

Maurice Bersan
 

Thanks Raj, I tried 11.0555 but it was very much worse, however the setting I am using now is 11.055.995 and it sounds normal now.
Thanks again
Maurice

On 7 Nov 2019 1:47 p.m., Raj vu2zap <rajendrakumargg@...> wrote:

Set it to 11.0555 and see if it sounds fine and no carrier leak!

Raj

At 06/11/2019, you wrote:
>Thanks the help so far, yes it is a calibration/bfo settings issue. I still struggle to set them correctly. So I'm using factory default settings at the moment, works ok but sounds like it has to much trebble.
>Cheers
>Maurice
>Vk6hly