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Re: Distorted audio signal on shortwave (rx!)

 

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@Spence: well great Idea!
I will record a video and upload it to youtube. Then I share the link here...

It takes a couple of days since I am in vacation now.

@Andy, I speak about low frequencies (ca. 300 ... 800 Hz) and not low volume.
The effect can be shown by putting a sound generator at the input of the TDA and wobble the frequency then...

I'll be back after my holidays...

73, Tom


Am 18.08.2022 um 23:33 schrieb Spence M0STO via groups.io:

Can I please inject a suggestion.....?

Make a short video and post it on YouTube as private for those with a link so we can all see the issue.

? Failing that I will create a guest account on my FTP server and upload it there!

De Spence M0STO?

Sent while portable! please excuse typos.

On 18 Aug 2022, at 22:03, Andy Bosworth <sidthepop@...> wrote:

When you say "at low audio frequencies", do you mean low frequencies, or low AF Gain on front panel?

I think there may be a translation problem.

Regards

Andy


Re: Distorted audio signal on shortwave (rx!)

 

开云体育

Can I please inject a suggestion.....?

Make a short video and post it on YouTube as private for those with a link so we can all see the issue.

? Failing that I will create a guest account on my FTP server and upload it there!

De Spence M0STO?

Sent while portable! please excuse typos.

On 18 Aug 2022, at 22:03, Andy Bosworth <sidthepop@...> wrote:

When you say "at low audio frequencies", do you mean low frequencies, or low AF Gain on front panel?

I think there may be a translation problem.

Regards

Andy


Re: Distorted audio signal on shortwave (rx!)

 

When you say "at low audio frequencies", do you mean low frequencies, or low AF Gain on front panel?

I think there may be a translation problem.

Regards

Andy


Re: Distorted audio signal on shortwave (rx!)

 

开云体育

...as I wrote "also at the speaker jack"

It is the same with an external speaker.

Yes, I mean regular SSB on hf bands ...

73, Tom

Am 17.08.2022 um 22:49 schrieb Andrew Lenton:

Shortwave? Do you mean HF, first try an external speaker.

73

Andrew?

Remember AM shortwave broadcast station require a wider filter 6 KHz

Get


Re: Distorted audio signal on shortwave (rx!)

 

Shortwave? Do you mean HF, first try an external speaker.

73

Andrew?

Remember AM shortwave broadcast station require a wider filter 6 KHz

Get


Distorted audio signal on shortwave (rx!)

 

Hi all,

I have noticed on my "new" FT-847 that the receive audio signal on
shortwave is distorted at low audio frequencies. I suspect that the
TDA2003H has a defect. At the input pin the signal still looks good, but
at the output (also at the speaker jack) it is distorted. Does anyone
know the problem? The capacitors in this area look good.

Also, the attenuator does not work on shortwave. If you press the
button, the audio signal crackles.

Bad shopping?
73 de Tom, DJ6TB


Re: FAST button not working through mic jack

 

Cool

Get


Re: FAST button not working through mic jack

Max Donoghue
 

Disregard, got it.


On Fri, Aug 12, 2022 at 12:13 PM Max Donoghue via <ve3tmt=[email protected]> wrote:
So the next question is...how do I center the SHIFT control. I'm a little confused by the instructions in the SM.

Max


Re: FAST button not working through mic jack

Max Donoghue
 

So the next question is...how do I center the SHIFT control. I'm a little confused by the instructions in the SM.

Max


Re: FAST button not working through mic jack

Max Donoghue
 

Solved,

R6573 was open, jumpered with a 2K and FAST button now works from the mic.

Max


Re: FAST button not working through mic jack

Max Donoghue
 

I've measured for continuity between the components. No open traces.

R6568 is reading good at 100.7K

R6571 and R6572 are reading a bit high at 2.8K (SM shows 1K)

R6573, in series with the FST line is showing open. No reading across it at all


Re: FAST button not working through mic jack

Max Donoghue
 

I've got nothing on pin 4. I shorted it to pin 5 without success. Also tried 10 between pin 2 (5V) and pin 4 without success.

I've got it apart now taking a look

Max


Re: FAST button not working through mic jack

 

开云体育

Some radios have Pin4 connected with Pin2 (+5V).

Shorting Pin4 with Pin5 enables FAST.

Check on the radio that Pin4 has no voltage, if so take appropriate measures for correct wiring.


On 2022-08-12 10:56 AM, Greg D wrote:

I have the MH-1b8 mike on my 847, and the Fast button works as expected.?

Greg? KO6TH


William Shadid wrote:

Max,

?

I first ran into this difference years ago when trying to use my MD-1 Desk Microphone with a newly acquired (at the time) FT-920 Transceiver. If you look at the schematic of, for instance, the MD-1 compared to the MD-100 you can see the difference. BUT, note also that there was a later version of the MD-1 that had the updated wiring. Seems, if I recall correctly, that there was an MD-1b8 that I had but that the later version, MD-1c8, had that wiring updated. I have since updated both MD-1's that I have here to "c8 status." If you cannot find the details, let me know and I can do some digging here to help you.

?

73, Bill, W9MXQ

?

From: [email protected] <[email protected]> On Behalf Of Max Donoghue
Sent: Wednesday, August 10, 2022 2:32 PM
To: [email protected]
Subject: Re: [YaesuFT847] FAST button not working through mic jack

?

Thanks Bill,

I'll have to trace the lines from the mic jack to the front panel board and try and sort out which is which.

Max


Re: FAST button not working through mic jack

 

开云体育

I have the MH-1b8 mike on my 847, and the Fast button works as expected.?

Greg? KO6TH


William Shadid wrote:

Max,

?

I first ran into this difference years ago when trying to use my MD-1 Desk Microphone with a newly acquired (at the time) FT-920 Transceiver. If you look at the schematic of, for instance, the MD-1 compared to the MD-100 you can see the difference. BUT, note also that there was a later version of the MD-1 that had the updated wiring. Seems, if I recall correctly, that there was an MD-1b8 that I had but that the later version, MD-1c8, had that wiring updated. I have since updated both MD-1’s that I have here to “c8 status.” If you cannot find the details, let me know and I can do some digging here to help you.

?

73, Bill, W9MXQ

?

From: [email protected] <[email protected]> On Behalf Of Max Donoghue
Sent: Wednesday, August 10, 2022 2:32 PM
To: [email protected]
Subject: Re: [YaesuFT847] FAST button not working through mic jack

?

Thanks Bill,

I'll have to trace the lines from the mic jack to the front panel board and try and sort out which is which.

Max



Re: FAST button not working through mic jack

William Shadid
 

开云体育

Max,

?

I first ran into this difference years ago when trying to use my MD-1 Desk Microphone with a newly acquired (at the time) FT-920 Transceiver. If you look at the schematic of, for instance, the MD-1 compared to the MD-100 you can see the difference. BUT, note also that there was a later version of the MD-1 that had the updated wiring. Seems, if I recall correctly, that there was an MD-1b8 that I had but that the later version, MD-1c8, had that wiring updated. I have since updated both MD-1’s that I have here to “c8 status.” If you cannot find the details, let me know and I can do some digging here to help you.

?

73, Bill, W9MXQ

?

From: [email protected] <[email protected]> On Behalf Of Max Donoghue
Sent: Wednesday, August 10, 2022 2:32 PM
To: [email protected]
Subject: Re: [YaesuFT847] FAST button not working through mic jack

?

Thanks Bill,

I'll have to trace the lines from the mic jack to the front panel board and try and sort out which is which.

Max


Re: FAST button not working through mic jack

Max Donoghue
 

Thanks Bill,

I'll have to trace the lines from the mic jack to the front panel board and try and sort out which is which.

Max


Re: FAST button not working through mic jack

William Shadid
 

开云体育

Early Yaesu 9-pin connector wiring used two different common lines – so they are not identical but work on most functions, interchangeably.

?

The two different 8-pin microphone designs show up among several different ones in my collection of Yaesu radios and their respective OEM microphones. For instance, my original version MD-1 is not wired from the factory quite like my MD-100 – and they are not 100% interchangeable.

?

73, Bill, W9MXQ

?

?

From: [email protected] <[email protected]> On Behalf Of William Shadid
Sent: Tuesday, August 09, 2022 7:04 PM
To: [email protected]
Subject: Re: [YaesuFT847] FAST button not working through mic jack

?

Max,

?

I had a problem with my FT-847 in the same way. It was the microphone – an older model 8-pin model with the UP, DOWN, and FAST buttons – but the FAST did not work. When I used the MH-31B8 Microphone (that was supplied originally with the radio), all worked fine. Some earlier model Yaesu microphones work fine for audio and PTT activation, and even UP and DOWN – but they may have some problems in things like that FAST control.

?

73, Bill, W9MXQ

?

From: [email protected] <[email protected]> On Behalf Of Max Donoghue
Sent: Tuesday, August 09, 2022 2:59 PM
To: [email protected]
Subject: [YaesuFT847] FAST button not working through mic jack

?

Well now that the UHF transmit problem was resolved (thank you again to everyone), my next issue is the FAST function does not work from the microphone or by shorting the appropriate pins on the mic jack.

When I press the FAST button on the front panel the icon shows up and tuning increases as expected, so it is working from the panel. I'd like to resolve this as I need to align the SHIFT control and I can't get in to the adjustment menu without the FAST button working on the mic.

Max


Re: FAST button not working through mic jack

Max Donoghue
 

I do not believe it is a mic issue. I checked the wiring and it is all intact. According to the schematic, shorting pin 4 (FAST) on the mic jack should activate that function. It does not.

I also looked on the back of the front panel and the wiring seems to be in place as well.

Max


Re: FAST button not working through mic jack

 

开云体育

Ok I will look into this, it will be something silly!

?

73

?

Andrew

?

From: [email protected] [mailto:[email protected]] On Behalf Of Max Donoghue
Sent: 09 August 2022 20:59
To: [email protected]
Subject: [YaesuFT847] FAST button not working through mic jack

?

Well now that the UHF transmit problem was resolved (thank you again to everyone), my next issue is the FAST function does not work from the microphone or by shorting the appropriate pins on the mic jack.

When I press the FAST button on the front panel the icon shows up and tuning increases as expected, so it is working from the panel. I'd like to resolve this as I need to align the SHIFT control and I can't get in to the adjustment menu without the FAST button working on the mic.

Max


Re: FAST button not working through mic jack

 

开云体育

I have seen (2) Yaesu microphones not wired correctly for the radios they were attached to. One was simple miswire, the other was not soldered, it had heat-shrink applied to one of the wires insulating it.

Should be easy enough to pull the body of the plug apart to inspect the wiring.

?Micky - K1XH


On 2022-08-09 08:04 PM, William Shadid wrote:

Max,

?

I had a problem with my FT-847 in the same way. It was the microphone – an older model 8-pin model with the UP, DOWN, and FAST buttons – but the FAST did not work. When I used the MH-31B8 Microphone (that was supplied originally with the radio), all worked fine. Some earlier model Yaesu microphones work fine for audio and PTT activation, and even UP and DOWN – but they may have some problems in things like that FAST control.

?

73, Bill, W9MXQ

?

From: [email protected] <[email protected]> On Behalf Of Max Donoghue
Sent: Tuesday, August 09, 2022 2:59 PM
To: [email protected]
Subject: [YaesuFT847] FAST button not working through mic jack

?

Well now that the UHF transmit problem was resolved (thank you again to everyone), my next issue is the FAST function does not work from the microphone or by shorting the appropriate pins on the mic jack.

When I press the FAST button on the front panel the icon shows up and tuning increases as expected, so it is working from the panel. I'd like to resolve this as I need to align the SHIFT control and I can't get in to the adjustment menu without the FAST button working on the mic.

Max

?