I built this kit many years ago and put it in and enclosure and everything - might have even bench tested it. Then life happened and now I'm trying to figure out which RXTXv6.2 I have. I looked through all of the file areas and nothing matches up. The kit I built has a daughter board with a 28.2076 and 28.060 crystals. I can't find any reference to the 28.2076 anywhere. Any help would be appreciated.

73

On 21/02/2024 07:04, Brian Teravskis via groups.io wrote:

The kit I built has a daughter board with a 28.2076 and 28.060 crystals.

Brian,

My guess is a version of the RXTX 6.2, maybe a different band pair or different centre frequency.


http://www.wb5rvz.com/sdr/RXTX62/

73 Alan G4ZFQ

www.wb5rvz.com/sdr/rxtx62/II_localoscillator.htm<http://www.wb5rvz.com/sdr/rxtx62/II_localoscillator.htm>


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________________________________
From: softrock40@groups.io <softrock40@groups.io> on behalf of Brian Teravskis via groups.io <bkt0031@...>
Sent: Wednesday, February 21, 2024 2:04:38 AM
To: softrock40@groups.io <softrock40@groups.io>
Subject: [softrock40] Trying to figure out which RXTXv6.2 this is...

I built this kit many years ago and put it in and enclosure and everything - might have even bench tested it. Then life happened and now I'm trying to figure out which RXTXv6.2 I have. I looked through all of the file areas and nothing matches up. The kit I built has a daughter board with a 28.2076 and 28.060 crystals. I can't find any reference to the 28.2076 anywhere. Any help would be appreciated.

73

From memory....40m kit with center freq of 7015kHz and 7052kHz, +/- soundcard sample width. Xtal/4.

Dave kx3dx

http://www.wb5rvz.com/sdr/RXTX62/II_LocalOscillator.htm

this one should work

Ben

________________________________
From: softrock40@groups.io <softrock40@groups.io> on behalf of Ben Cherry <satman39@...>
Sent: Wednesday, February 21, 2024 2:44 PM
To: softrock40@groups.io <softrock40@groups.io>
Subject: Re: [softrock40] Trying to figure out which RXTXv6.2 this is...

www.wb5rvz.com/sdr/rxtx62/II_localoscillator.htm<http://www.wb5rvz.com/sdr/rxtx62/II_localoscillator.htm><http://www.wb5rvz.com/sdr/rxtx62/II_localoscillator.htm<http://www.wb5rvz.com/sdr/rxtx62/II_localoscillator.htm>>


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________________________________
From: softrock40@groups.io <softrock40@groups.io> on behalf of Brian Teravskis via groups.io <bkt0031@...>
Sent: Wednesday, February 21, 2024 2:04:38 AM
To: softrock40@groups.io <softrock40@groups.io>
Subject: [softrock40] Trying to figure out which RXTXv6.2 this is...

I built this kit many years ago and put it in and enclosure and everything - might have even bench tested it. Then life happened and now I'm trying to figure out which RXTXv6.2 I have. I looked through all of the file areas and nothing matches up. The kit I built has a daughter board with a 28.2076 and 28.060 crystals. I can't find any reference to the 28.2076 anywhere. Any help would be appreciated.

73

Yeah, I'll have to dig out the oscilloscope and power supply to figure it out (we are in the middle of a house remodel and everything is packed away in boxes). Thanks for the pointers.

While getting my oscilloscope and power supply out I found a bubble mailer package that had all of the SoftRock kit bags and labels in it that I've purchased over the years. In this package I found that this is a RXTXv6.2 15m/17m kit. I also found that I had one of the crystal markings incorrect as it is really 28.2C76. With the oscilloscope the two frequencies the daughter board generates are 84.7325 MHz and 84.2465 MHz. The schematic indicates the crystals are 28.244 MHz and 28.060 MHz which pretty much work out for third overtone on the output of the board. The output of the divider ended up being 21.1831 MHz and 21.0615 MHz respectively. I can understand how this will work on 15 meters, but I have no idea how this works on 17m. Not a big deal really as it is highly unlikely I will be working 17m anyway.

It is a good thing I found that mailer package because in the daughter board bags there were two 10K 1/8W axial resistors that were supposed to be installed flat on the main board for R59 and R60. Looking at the parts I'm pretty sure I could not really figure out how to mount them flat on the main board, and I was probably planning on mounting them flat on the back side of the board and forgot. I decided today to instead use two 0805 SMD 10K resistors which I soldered to the resistor pads on the back side of the board. Prior to installing those resistors I noticed that occasionally the oscillator would not start, but after installing those resistors it seems to start every time I apply voltage to the board.

Thanks again and 73

I thought that for some frequencies they might run at 3/4 or 4/3 frequency or something like that, such that they alias down to baseband, probably with a I and Q swapped.