profdc9
commented
11 months ago Here are a few hints:
- Make sure the output of your soundcard is turned up to maximum volume. You may also want to fit a jumper onto JP6 (this will involve temporarily removing the LCD). The radio measures the audio frequency from the sound card. It can be a square wave, so it's ok to have it distorted. It's not like a normal transceiver where an overdriven input creates harmonics.
- The mode is not actually used in Ext mode, it is just set to CW to force the SSB code to turn off. The code below it takes control of the frequenc
- When you are in CW mode, the BFO is set to 667 Hz below the selected VFO frequency so that the CW creates a beat of 667 Hz (the sidetone frequency). So for example, if you tune 14074000 Hz, and you are in CW mode, before the Ext mode is selected, you should hear a faint signal from the BFO of 14074000 Hz - 667 Hz = 14073333 Hz. Once the Ext mode is selected, the BFO should be at 14074000 Hz. That's why it is jumping up by about 700 Hz.
- When the soundcard sends a tone, for example 1.2 kHz, the radio should transmit a frequency of 14074000 + 1200 Hz = 14075200 Hz. If this is not the case then there is something wrong.
Check these things and see if that helps.
73, Dan KW4TI
When external control mode is selected, the BFO should increase to
- The operation in Ext mode doesn't depend on the selected mode.
On Sat, Oct 21, 2023 at 11:24 AM larryl719 @.***> wrote:
Hi,
First, I'd like to say Thanks! This is a very interesting radio and was easy to assemble and play with. I have built a full set of band boards and am starting to put it to use.
Maybe I'm missing something (that would be great!) but when I'm trying to get it to operate on FT8, I see a couple of things happening:
1.
I need to use EXT mode to control the transceiver and it says it is the way to do it. When I enter EXT mode and the words "EXT Mode" appear and then go away, I can hear the frequency of the receiver shifting. My measurements seem to indicate a move of about 700Hz. If I keep the radio tuned to 14.074, my audio output ends up 700Hz too high, and in many cases, it's above the audio passband of the signal so that no one can hear me. Tuning lower might be the answer but then there appears to be another issue. (below) When exiting EXT mode, the frequency returns to the original value. I only really figured this out by using another radio to monitor my transmission and see that my signal was above the audio passband used for FT8. 2.
When transmitting FT8 signals in EXT mode (and possibly shifting the frequency), I notice that it sounds "choppy" with some additional "artifacts" on the signal; normal FT8 signals tend to sound very smooth. When I use "Tune" mode in WSJTX, the signal is very clean and sounds normal. (My X6100 shows the audio spectrum on the display and there are "lobes" at lower amplitude under the main signal. Also, the signal sounds very different on the X6100 than other FT8 signals.) 3.
In the manual there are instructions (In the EXT mode description) to tune to the upper sideband (14.074) when doing FT8. This is the normal way of doing FT8, so that's not unusual. But, in looking at the code (and watching what happens), when EXT mode has been activated the mode is changed to CW and stays there. While I don't think that is an issue exactly, I was wondering why change it and whether it might be related to the above problems in some way. 4.
I'm sorry to say I haven't tested out the other modes like SCAMP or RTTY mostly because 10m is really open so far this year and I'm having a great time making QRP contacts on 10m all over the world. That has also meant that I've spent a lot of time trying to get a bit more power out at 10m (with "normal" builds of the boards I'm getting about 0.5W out). IF everything else was working well, I'd enjoy the challenge of the QRP contacts at 0.5W, but so far the issues above are keeping me from making contacts.
If there is anything I can do or try, please let me know, I'd be happy to help. I haven't tried reprogramming the radio yet because I wanted to spend more time with the original design before I mess with it in any way.
Thanks again! Larry, WB6JSO @.***)
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larryl719
Hi,
First, I'd like to say Thanks! This is a very interesting radio and was easy to assemble and play with. I have built a full set of band boards and am starting to put it to use.
Maybe I'm missing something (that would be great!) but when I'm trying to get it to operate on FT8, I see a couple of things happening:
I need to use EXT mode to control the transceiver and it says it is the way to do it. When I enter EXT mode and the words "EXT Mode" appear and then go away, I can hear the frequency of the receiver shifting. My measurements seem to indicate a move of about 700Hz. If I keep the radio tuned to 14.074, my audio output ends up 700Hz too high, and in many cases, it's above the audio passband of the signal so that no one can hear me. Tuning lower might be the answer but then there appears to be another issue. (below) When exiting EXT mode, the frequency returns to the original value. I only really figured this out by using another radio to monitor my transmission and see that my signal was above the audio passband used for FT8.
When transmitting FT8 signals in EXT mode (and possibly shifting the frequency), I notice that it sounds "choppy" with some additional "artifacts" on the signal; normal FT8 signals tend to sound very smooth. When I use "Tune" mode in WSJTX, the signal is very clean and sounds normal. (My X6100 shows the audio spectrum on the display and there are "lobes" at lower amplitude under the main signal. Also, the signal sounds very different on the X6100 than other FT8 signals.)
In the manual there are instructions (In the EXT mode description) to tune to the upper sideband (14.074) when doing FT8. This is the normal way of doing FT8, so that's not unusual. But, in looking at the code (and watching what happens), when EXT mode has been activated the mode is changed to CW and stays there. While I don't think that is an issue exactly, I was wondering why change it and whether it might be related to the above problems in some way.
I'm sorry to say I haven't tested out the other modes like SCAMP or RTTY mostly because 10m is really open so far this year and I'm having a great time making QRP contacts on 10m all over the world. That has also meant that I've spent a lot of time trying to get a bit more power out at 10m (with "normal" builds of the boards I'm getting about 0.5W out). IF everything else was working well, I'd enjoy the challenge of the QRP contacts at 0.5W, but so far the issues above are keeping me from making contacts.
If there is anything I can do or try, please let me know, I'd be happy to help. I haven't tried reprogramming the radio yet because I wanted to spend more time with the original design before I mess with it in any way.
Thanks again! Larry, WB6JSO (wb6jso@hotmailDOTcom)