Troubleshooting ADX-S Receiver Noise

#4652

I'm using my ADX-S with a DigiRig and WSJT-X running on both Armbian OS and MacOS machines. I have successfully completed FT8 QSOs and have been spotted transmitting WSPR. However in all modes I'm encountering what appears to be persistent harmonic noise across the spectrum. I've done everything possible to eliminate possible noise sources in the shack by shutting down and disconnecting as much equipment as possible when testing with the ADX-S. When using my other transceivers (FT-817ND and the IC-7300) I have no indications of any spurious noise injection or RFI infiltration. My sense is this noise is being generated by the ADX-S circuit, perhaps by a bad connection or an incorrect component value. I have attached several screen photos that show these noise harmonics in the waterfall display.?

I would appreciate your insight and suggestions on how to proceed with troubleshooting. Thanks.

73,
Mark WB8BCU

FT8 waterfall on Armbian.jpeg

FT8 waterfall on MacOS.jpeg

WSPR waterfall.jpeg

Re: KT- CP3 Radio a short test video

#4651

开云体育

A dental floss plastic case will be a good home for the KT receiver.

Thanks,

Adam

Show quoted text

在 2023年12月19日，08:28，Adam Rong via groups.io <rongxh@...> 写道：

?Barb,

A long wire of 5 meters will help if it is connected to the whip antenna. Even without the additional length, the whip is doing well here in China as the local SW stations are so strong.

Thanks,
Adam

在 2023年12月19日，07:13，wb2cba@... 写道：

?
Adam,

I agree on red led instead of ?green led for tuning. I must confess that I didn’t read your build manual and was rushing to finish and test. Didn’t pay much attention which led goes to which and abd ?ended up with this selection!:) Will swap the leds for sure.
?

I don’t have a ham antenna setup at home. I wil try with my endfed half wave field antenna soon for SW this weekend.

I am still blown away with the quality of FM reception of this little radio. Amazing.

--
73

Barb WB2CBA

Re: KT- CP3 Radio a short test video

#4650

开云体育

Barb,

A long wire of 5 meters will help if it is connected to the whip antenna. Even without the additional length, the whip is doing well here in China as the local SW stations are so strong.

Thanks,

Adam

Show quoted text

在 2023年12月19日，07:13，wb2cba@... 写道：

?
Adam,

I agree on red led instead of ?green led for tuning. I must confess that I didn’t read your build manual and was rushing to finish and test. Didn’t pay much attention which led goes to which and abd ?ended up with this selection!:) Will swap the leds for sure.
?

I don’t have a ham antenna setup at home. I wil try with my endfed half wave field antenna soon for SW this weekend.

I am still blown away with the quality of FM reception of this little radio. Amazing.

--
73

Barb WB2CBA

Re: KT- CP3 Radio a short test video

#4649

Adam,

I agree on red led instead of ?green led for tuning. I must confess that I didn’t read your build manual and was rushing to finish and test. Didn’t pay much attention which led goes to which and abd ?ended up with this selection!:) Will swap the leds for sure.
?

I don’t have a ham antenna setup at home. I wil try with my endfed half wave field antenna soon for SW this weekend.

I am still blown away with the quality of FM reception of this little radio. Amazing.

--
73

Barb WB2CBA

Re: KT- CP3 Radio a short test video

#4648

开云体育

Barb,

Thanks for the photos and video. It looks great. One little thing is that it is better to use the red LED for tuning as it is brighter.

Try to connect to your ham radio antenna and experience the amazing performance of SW and MW bands. The short whip is just to amaze you guys, not a best performer.

Thanks,

Adam

On 2023/12/19 1:24, wb2cba@... wrote:

Show quoted text

Adam mailed me a KT-CP3 radio kit which I received yesterday and build it in half an hour! It was a breeze to build this little kit! Then I connected it to my external speaker and shoot a short test video which is posted on my cgannel on youtube:

Adam thank you for gifting me this little wonder.?

Here are some photos of my build:

--
73

Barb WB2CBA

KT- CP3 Radio a short test video

#4647

Adam mailed me a KT-CP3 radio kit which I received yesterday and build it in half an hour! It was a breeze to build this little kit! Then I connected it to my external speaker and shoot a short test video which is posted on my cgannel on youtube:

Adam thank you for gifting me this little wonder.?

Here are some photos of my build:

--
73

Barb WB2CBA

Re: CPK-3 KT is formal

#4646

开云体育

Thanks guys for the orders! I have shipped the first batch earlier today, and more to follow tomorrow. Based on the feedback from my shipping agency, the post office tracked air parcel is quite busy so please expect delay of up to two weeks. Appreciate your patience.

Thanks,

Adam

On 2023/12/17 19:57, Adam Rong via groups.io wrote:

Show quoted text

Guys,

Based on the very positive feedback from our domestic customers, I have updated the web store to include CPK-3 KT Receiver. The unit price for the kit and the mini whip antenna including tracked air shipping is 14.5 USD. The formal kits are the same as the beta kits.

The documentations are stored in the File section. Although the manual is still draft2, it is good enough to support the kit building. As always, I will update it along the way you test the beta kits.

/g/crkits/files/KT

Thanks,

Adam

CPK-3 KT is formal

#4645

开云体育

Guys,

Based on the very positive feedback from our domestic customers, I have updated the web store to include CPK-3 KT Receiver. The unit price for the kit and the mini whip antenna including tracked air shipping is 14.5 USD. The formal kits are the same as the beta kits.

The documentations are stored in the File section. Although the manual is still draft2, it is good enough to support the kit building. As always, I will update it along the way you test the beta kits.

/g/crkits/files/KT

Thanks,

Adam

File /KT/CPK-3 KT Receiver Assembly Manual(draft2).pdf updated #file-notice

Group Notification

#4644

The following files and folders have been updated in the Files area of the [email protected] group.

/KT/CPK-3 KT Receiver Assembly Manual(draft2).pdf

By: Adam Rong <rongxh@...>

Description:
Updated the draft manual, good for beta testers

Re: KT Receiver Domestic Report

#4643

开云体育

Thanks for the first report. It looks good.

VAR - band switch by SPAN potentiometer (FM/MW/SW)

FAV - band setting by 5.1k resistor ~ SW 13-14.3MHz

Thanks,

Adam

On 2023/12/17 5:23, JP McGinley wrote:

Show quoted text

? Took me about 30-40 minutes start to finish, including cleaning flux off of board. Soldered radio IC first. I am still trying to see what the FAV/VAR pins tune, appears to be maybe SW 12Mhz.?

?Still twisting the dial, receiving local FM broadcasters. Will try SW broadcasters tonight.?

JP

KA3BWP?

On Dec 15, 2023, at 8:48 PM, Adam Rong <rongxh@...> wrote:

? Looking forward to the first report from abroad.

Thanks,
Adam

在 2023年12月15日，07:42，JP McGinley <j.p.mcg@...> 写道：

?Adam,
? I received mine on 13 Dec. Going to heat the soldering iron this weekend. Thank you
JP
KA3BWP

Re: KT Receiver Domestic Report

#4642

开云体育

? Took me about 30-40 minutes start to finish, including cleaning flux off of board. Soldered radio IC first. I am still trying to see what the FAV/VAR pins tune, appears to be maybe SW 12Mhz.?

?Still twisting the dial, receiving local FM broadcasters. Will try SW broadcasters tonight.?

JP

KA3BWP?

Show quoted text

On Dec 15, 2023, at 8:48 PM, Adam Rong <rongxh@...> wrote:

?Looking forward to the first report from abroad.

Thanks,
Adam

在 2023年12月15日，07:42，JP McGinley <j.p.mcg@...> 写道：

?Adam,
? I received mine on 13 Dec. Going to heat the soldering iron this weekend. Thank you
JP
KA3BWP

Re: KT Receiver Domestic Report

#4641

开云体育

Looking forward to the first report from abroad.

Thanks,

Adam

Show quoted text

在 2023年12月15日，07:42，JP McGinley <j.p.mcg@...> 写道：

?Adam,
? I received mine on 13 Dec. Going to heat the soldering iron this weekend. Thank you
JP
KA3BWP

Re: KT Receiver Domestic Report

#4640

Adam,
? I received mine on 13 Dec. Going to heat the soldering iron this weekend. Thank you
JP
KA3BWP

ADX-S Engineering Change Notice 20231213

#4639

Guys,

We have upgraded the shipping firmware from V1.1 to V1.3 so we ask you to add a 3mm red LED to the CAL and GND test pins at least. You can find the LED in the kit in pink plastic bags. If you fail to do so, you will get poor receiver performance.

The adding of LED is part of the RX modifications outlined in the chapter Modifications in the assembly manuals. It is strongly recommended if you can apply all the RX modifications.

Thanks,

Adam

KT Receiver Domestic Report

#4638

开云体育

Guys,

While you are still waiting for the parcel patiently, about 6 dozens of domestic customers are enjoying this tiny radio now. A newbie told me in my wechat group that he just bought a soldering iron and KT is his first soldering project, but it is a total success. People sent many videos to demo their own KT radio.

I hope you enjoy this radio kit as much as domestic customers do.

Thanks,

Adam

Re: File /KT/CPK-3 KT Receiver Assembly Manual(draft).pdf uploaded #file-notice

#4637

开云体育

This blog further explains the schematic:

Thanks,

Adam

Show quoted text

在 2023年12月9日，01:31，Wayne Steury <waynesteury@...> 写道：

?
Adam, thank you for sending this helpful information about this receiver kit. I assume that R2 can be my band of choice according to what Ohms I have on my Resistor (According to the chart).? Neat!

I am excited to build this and see what it will do. Thank you for giving us this privilege to try the beta version at minimum cost.

Wayne N9EGT?
western colorado?

On Fri, Dec 8, 2023 at 8:20?AM Group Notification <[email protected]> wrote:

The following files and folders have been uploaded to the Files area of the [email protected] group.

/KT/CPK-3 KT Receiver Assembly Manual(draft).pdf

By: Adam Rong <rongxh@...>

Description:
Draft manual, good for beta testers

Re: File /KT/CPK-3 KT Receiver Assembly Manual(draft).pdf uploaded #file-notice

#4636

Adam, thank you for sending this helpful information about this receiver kit. I assume that R2 can be my band of choice according to what Ohms I have on my Resistor (According to the chart).? Neat!

I am excited to build this and see what it will do. Thank you for giving us this privilege to try the beta version at minimum cost.

Wayne N9EGT?

western colorado?

Show quoted text

On Fri, Dec 8, 2023 at 8:20?AM Group Notification <[email protected]> wrote:

The following files and folders have been uploaded to the Files area of the [email protected] group.

/KT/CPK-3 KT Receiver Assembly Manual(draft).pdf

By: Adam Rong <rongxh@...>

Description:
Draft manual, good for beta testers

File /KT/CPK-3 KT Receiver Assembly Manual(draft).pdf uploaded #file-notice

Group Notification

#4635

The following files and folders have been uploaded to the Files area of the [email protected] group.

/KT/CPK-3 KT Receiver Assembly Manual(draft).pdf

By: Adam Rong <rongxh@...>

Description:
Draft manual, good for beta testers

Re: PIXIE2023: One of the cleanest output Pixie?

#4634

开云体育

Thanks for sharing. Nice blue box. The final 2N2222 might help the RF output if you QSY to 20m band.

Thanks,

Adam

Show quoted text

在 2023年12月8日，01:41，Wayne Steury <waynesteury@...> 写道：

?I have been very pleased with my pixie 2023 and it’s clear receiver and good transmit output. I converted it to 20 m by changing the final output filter to 56 uH , 220 pf 0n both caps. Crystal on 20 meters. Final transistor 2n2222. ?12 battery volts. N9EGT?

PIXIE2023: One of the cleanest output Pixie?

#4633

I have been very pleased with my pixie 2023 and it’s clear receiver and good transmit output. I converted it to 20 m by changing the final output filter to 56 uH , 220 pf 0n both caps. Crystal on 20 meters. Final transistor 2n2222. ?12 battery volts. N9EGT?