Hello!? I installed a sound card, checked drive levels, and monitored my psk31 via a online sdr that could hear me. I was thrilled to see my signal...I was getting out!? I was also sending a mirror below my signal. I've been told my radio does this, and here I could capture it without using my own SDR. The online SDR was not over driven, as far as I can tell, so this looks like a problem on my end.? The ghost signal looks almost the same signal strength as my target frequency!? Is there anything I can do about this...or is this fixed with the inductors/relays?

And thank you all sooo much as always.

On 80M the relays make a big difference to spurs.

The ghost will be around -35db at the worst.. not stronger than that.
Reduce the drive and see what happens.

Raj

At 02-11-18, you wrote:

On Fri, Nov 02, 2018 at 01:03:40PM +0530, Raj vu2zap wrote:

On 80M the relays make a big difference to spurs.

The ghost will be around -35db at the worst.. not stronger than that.
Reduce the drive and see what happens.

This sounds more like opposite side band is not being suppressed
properly, but hard to tell without more information. If it's a filter
problem the signal will be inverted.

Raj

At 02-11-18, you wrote:

Hello! I installed a sound card, checked drive levels, and monitored my psk31 via a online sdr that could hear me. I was thrilled to see my signal...I was getting out! I was also sending a mirror below my signal. I've been told my radio does this, and here I could capture it without using my own SDR. The online SDR was not over driven, as far as I can tell, so this looks like a problem on my end. The ghost signal looks almost the same signal strength as my target frequency! Is there anything I can do about this...or is this fixed with the inductors/relays?

How far away from your main signal is it? Does it always appear below
your main signal by the same amount?

And thank you all sooo much as always.
[]

Diane
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Paranormal signal is about eyeballing 1400khz (I think??) below. Receiving websdr is miles away.?

If I reduce drive the ghost appears proportionally reduced.

? ?I was told by a club member that my radio was not suppressing the carrier. But I'm not smart enough to diagnose that, hence the pictures..hahah.

Don
Km4udx

On Fri, Nov 02, 2018 at 07:33:50AM -0700, Don - KM4UDX wrote:

Paranormal signal is about eyeballing 1400khz (I think??) below. Receiving websdr is miles away.?

I think you meant Hz not KHz.

If I reduce drive the ghost appears proportionally reduced.

? ?I was told by a club member that my radio was not suppressing the carrier. But I'm not smart enough to diagnose that, hence the pictures..hahah.

That's easy to check. Put the radio into transmit but do not feed
it any audio at all. Do you still see the signal? If so that's the carrier.
If it only appears with a tone into the radio then that's an opposite
side band suppression problem.

I see no attached graphics if you were trying to attach some.

Don
Km4udx

Diane
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Raj, Diane, and the group:? I got a better picture and annotated the signals.?
You also asked if I could TX without any audio. So I just hit the PTT with no voice and got a picture. I can see a what I think is a carrier. But I must defer to experts! I've tried to both insert and attach pictures. Thank you!!!
?

On Sat, Nov 03, 2018 at 08:14:36PM -0700, Don - KM4UDX wrote:

Raj, Diane, and the group:? I got a better picture and annotated the signals.?
You also asked if I could TX without any audio. So I just hit the PTT with no voice and got a picture. I can see a what I think is a carrier. But I must defer to experts! I've tried to both insert and attach pictures. Thank you!!!

Yes that's your suppressed carrier.

What I see is two sidebands of crud as well as your main signal
at 500 Hz away from the suppressed carrier. It's hard to tell but the
two sidebands look inverted from each other to me. I'd be looking at what the
audio going into the radio looks like next. Here I am making the assumption
the sideband filter is not knocking down the opposite sideband and
close to the suppressed carrier properly. If the audio going in does
not have that ~500Hz component then it must be in the radio.
Also, have you aligned the radio? That lower sideband looks a smidgen stronger
than the upper sideband to me.

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The audio input comes from fldigi to the sound card to a easydigi (audio transformer isolator)? then to the uBIT.? How do i to check for errant tones?

No I didn't align the rig....can I do that without test equip?

I sort of hate to use it as is, or am I being a weenie?

开云体育

Go find some carrier (or a CW signal) , set your radio on upper side band. and make sure that you can hear the carrier when you are below it in frequency, and NOT when you cross over and go above it. ? ?

On Sun, Nov 04, 2018 at 06:22:25AM -0800, Don - KM4UDX wrote:

The audio input comes from fldigi to the sound card to a easydigi (audio
transformer isolator)? then to the uBIT.? How do i to check for errant
tones?

Ideally you'd use a scope. The crud is close enough in to your suppressed
carrier you'd be able to hear it on a SSB receiver by zero beating
the carrier that is leaking. It appears you should hear it on both
upper and lower sideband at about 500Hz.

Your PSK31 signal is at 3581.140 which is 1.140 Khz above 3580 so you
might also see a much weaker image at 3578.860 Khz of your PSK signal.
If the ssb filter is properly set up you shouldn't see much at all at 3578.860
I can't tell if that's a trace of it on the left of your picture or not,
if it is, it looks well down from the main signal. (As Allison has pointed
out the carrier suppression could also be better. ) I'm surprised the
filter isn't knocking down the 500Hz crud more than that, hence my query
about alignment.

If you can listen to the crud on an external receiver it may give
you a clue as to what it is coming from. I'd also turn the sound card
down to 0 at the computer and see if you are still getting that crud.
It could be the sound card output amp clipping as well. Really
a scope would help a lot here. :-(

No I didn't align the rig....can I do that without test equip?

Yes there are guides in the wiki. It has been covered here.

I sort of hate to use it as is, or am I being a weenie?

Personally, I wouldn't.

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Diane and Gordon --

I'll read up and follow instructions for alignment and do the SSB receiver test.

Would the relay/inductor replacements help me here? Or are these different issues?

Thanks so much as always.

Don

On Mon, Nov 05, 2018 at 09:30:38AM -0800, Don - KM4UDX wrote:

Diane and Gordon --

A very quick test for you to try. Try keying your radio and then *short*
the audio input. It won't hurt a thing but if the crud goes away
then you know it's something you are injecting on the audio line.
The psk signal of course will also disapear and it won't make any
difference to the suppressed carrier.

I'll read up and follow instructions for alignment and do the SSB receiver test.

Would the relay/inductor replacements help me here? Or are these different issues?

No. That's a different problem.

Thanks so much as always.

Don

73 Diane VA3DB
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so I hit the PTT, counted a 3 seconds, and shorted the high side mic to ground.
Here is resultant pic.? Essentially I can't see much of a difference between the two states.
So this shows the carrier without modulation, right?? Does this point to anything I should do?

Thank you!!

t

yep. It means your audio input is putting that crud on the modulator and it's showing up on the air because of that.
Can you borrow a scope? ;)

I re-read your note, and I may have made a mistake.
I wasn't running psk when I did the carrier test.
I just pulled the pill bottle mic apart and used the PPT and? shorted the mic element to ground
Does this matter?

I know of people with scopes...I'll ask one of the technically sophisticated radio engineers (we have a few) in the local club to take a look at it. They have scopes and smarts.

Is this fixable, or just a feature of the design??

I've had good digital QSO's above 80m,
so I know it works (flaws and all...) with jt8, and all the other digital modes, for which I am VERY thankful.?
Fortunately, the digital modes are very forgiving of marginal signals....hahaha.

Don
km4udx

On Mon, Nov 05, 2018 at 07:29:34PM -0800, Don - KM4UDX wrote:

I re-read your note, and I may have made a mistake.
I wasn't running psk when I did the carrier test.
I just pulled the pill bottle mic apart and used the PPT and? shorted the mic element to ground
Does this matter?

Nope. But if you put the psk output back into the radio and see the
crud re-appear, you know where to look!

I know of people with scopes...I'll ask one of the technically sophisticated radio engineers (we have a few) in the local club to take a look at it. They have scopes and smarts.

Is this fixable, or just a feature of the design??

It doesn't look to me to be the radio.

I've had good digital QSO's above 80m,
so I know it works (flaws and all...) with jt8, and all the other digital modes, for which I am VERY thankful.?

Wait. This crud only appears on psk? Then it's something with your
computer program or audio card levels; Something else is going on and
not with the radio.

Fortunately, the digital modes are very forgiving of marginal signals....hahaha.

Don
km4udx

Diane
va3db
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Diane - the crud is in all modes, just easy to see on psk.? I have a date with a smart guy & his scope on Friday.