New HL2 user transmit issue

[KC3KOP]

Hello everyone,

My name is Ian - KC3KOP. I purchased the HL2 back in December 2025. I believe the T/R relay is buzzing horribly. This happens when I go into a dummy load or antenna. I have shut off the PA and tested for power at RF1. I currently do not have a meter to read that low accurately, but my meter on 5W range does have meter deflection when I put the HL2 in transmit. I have tried SDR console, SparkSDR and Thetis software so far with no success. I have tried the software on 3 different machines with different Ethernet cords. I plugged them in straight to the computer and a then into a network switch. With some basic network logging, the HL2 is using 44Mbps running 192k sample rate. I have pinged the HL2 and the following: 

32bytes of data sent, time less than 1ms TTL=128

I will take it apart this weekend and take pictures of the board. I do have a microscope with a camera so I can take picture of an area if needed.

 

I followed the instructions in this link https://github.com/softerhardware/Hermes-Lite2/wiki/Hardware and did not find any problems.

 

This is my first time posting and I am following tests and instructions from these links

https://github.com/softerhardware/Hermes-Lite2/wiki/Repair

https://github.com/softerhardware/Hermes-Lite2/wiki/No-Transmit

 

YouTube links to my Hermes Lite transmit issue.

Thetis https://www.youtube.com/watch?v=6F5svpJnh8w

Spark SDR https://www.youtube.com/watch?v=uEtFsAXg_-E

Thank You for any help

73

Ian – KC3KOP

[Volker E.]

Hi,

i have the same issue specially on 40m. 

When i lower the power for tuning, the problem most time is gone.

You can set the power for tuning settings in Thetis -> setup -> transmit -> tune section

I have no idea why this happens....

73
Volker, DL1VE

[Volker E.]

I have an idea....

How much voltage do you use? Maybe low voltage can be the problem. 

When i use my lifepo and the voltage drops to 12V i get often this problem. 

I think with the power supply and 13.8V i never had this issue.

73

Volker, DL1VE

[KC3KOP]

Thank You for the Reply.

I have adjusted the Tuning Power, I have it backed down in hopes that this issues does not ruin the board. I will work on trying a different power supply. At this point I am losing faith that this will solve it. I spent the weekend running my Flex at 100w off the same power supply. I measure 13.70VDC the plug. Center pin is positive. I have installed inline 3A fuses between the power supply and the hermes.

Thank you for the help

73

Ian

[Mike Lewis]

Did changing the latency setting improve anything?

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[Steve Haynal]

Hi Ian,

What is the temperature, current draw and SWR reported by software (preferably Quisk) during your TX attempts into a dummy load? Can you post a screenshot of your software filter settings?

Do you feel comfortable connecting a dummy load directly to the HL2 via the pins on the header? This is to determine if the problem is with the N2ADR board or the HL2.

If we can't figure out the issue, I will authorize a warranty return or exchange with Makerfabs.

73,

Steve

kf7o

[KC3KOP]

negative Mike, only thing that changes the sound of it is if I change the Sample Rate. That seems to speed up or down the buzz

73

Ian

[KC3KOP]

Steve, from the quick key up the temp in Thetis seems to rise very rapid. I unkey and it falls quick as well. I will try to get Quisk installed as I have not done that. It might be a couple of days as the next few days at my QTH will be busy. I can solder of to 

the header pins. I tested my Dummy load on 2 other Rigs with using the same coax and getting 1.0SWR. I did a ohm reading thru the coax to the DL and I am getting 55.8 ohms.

Thank You for your input

73

Ian

[Steve Haynal]

Hi Ian,

Thanks for the responses. I don't see any problems with the settings. In the past, there have been instances where some components were scraped off or shorted due to installing the heat shim. This caused extreme fast heating. Can you please send pictures of the area (2-3 inches square) around the mounting hole used to secure the heat shim, both top and bottom of the circuit board. We can check for any damaged components. Also, do you see the same behavior when operating the HL2 outside of the enclosure and with no heat shim? It is okay to briefly (5-10 seconds) transmit in this configuration, especially if the TX drive is lowered.

73,

Steve

kf7o

[KC3KOP]

Steve,

I got a chance to take the pictures and try to put the HL2 in TX without the shim outside of the case. I have not had time to install quisk as of now. I am including a link to the video I took of the troubleshooting. https://youtu.be/ph5SFgtl9FU

Thank You

73 

Ian

[KC3KOP]

Other attached pictures.

[Steve Haynal]

Hi Ian,

Thanks for the pictures and video. No components appear scraped off or damaged. In the video, you have the IO board installed. Does it chatter the same way when the IO board is removed? With the IO board removed and using your finger, can you identify exactly which relay is chattering?

73,

Steve

kf7o

[KC3KOP]

HI Steve,

I did not disconnect the filter board because you said something about possibly soldering on the header to hook up a DL without the filter board. The weird thing is you would think you can feel which component is causing that noise but you cant really tell. I think I have a mechanic stethoscope somewhere around the QTH, I might try that.

73

Ian

[Steve Haynal]

Hi Ian,

Please check L3 for damage. This is the large inductor associated with the final power amplifier regulator. If these are cracked, they can cause a buzz like you are hearing, especially one of higher frequency as heard in your video. Try placing your finger on that and surrounding components to see if behavior changes.

In the picture, I see an IO board, N2ADR filter board, and HL2 board. It would be helpful to remove the IO board and N2ADR board one by one to see if the problem goes with one of those boards. That way we can identify exactly which board should be replaced.

73,

Steve

kf7o

[KC3KOP]

Hi Steve,

I got the mess with the Hermes, and I believe the relay on the main board is doing the buzzing. I did take pictures of L1,2 and 3 with my microscope and will get them uploaded and share them with you. I put a fat sharpie marker (I know not the tool of choice) on all the relays and L1,2 and 3 and on the filter board you can hear single clicks on them depending on the band of course. the buzz I believe is very intense on that relay on the main board.

73

Ian