http://youtu.be/V0LCFHeUZfo
Although I passed the Radio Amatur theory exam in 1965 I never actually got my licence ( ticket) as I did not manage the then obligatory, for the UK, 12 word per minuet Morse. Listening to the ham band for the first time in 45 years or so I found that my ears could read the "CQ" and "DE" but nothing else . Could I have another go at leaning morse ? and why not use the Lab 8 to try and decode and rather than use a modern receiver how about resurrecting my BC348 communications receiver at the same time, again unused for 45 years or so.
This is what started this project and alone the way has been added a 1960's Solatron valve oscilloscope, why do my projects always grow arms and legs ?
We have
"short" long wire antenna "tree to shed", 9:1 ballam, 1930's BC348 -R valve ( tube) receiver, 1970's Brookdeal AC amplifier ( that's the box with the meter ), bread boarded charge pump and comparator to demodulate the AF ( that's the spaghetti sitting on the Brookdeal ), 1960's Solatron valve dual beam scope ( powered by the variac as I'm still not ready to give it full line voltage), the Lab 8/E.
Iv ended up using most the Lab8's extra laboratory peripherals, I/P is one a bit on the DR8-EA digital I/O, the DK8-ES real time clock does the mark and space timing, and the VC8-E displays this on the Tek 611 .
The A/D converter is used with the 4 front panel pots to input dot/dash and space discriminator thresholds.
I cheated a little bit with the software by writing the source on the " console" PC using notepad and initially uploading this to the 8 and running Pal8 under OS8 to assemble, then debug using ODT. I had forgotten how slow this could be so after the 3rd or 4th iteration I changed to using PALBAR and just transferring the binary, MUCH faster.
The actual decode is still fairly error prone and there is a good deal of "driving" involved, the weakest bit is the CW demod, needs a very good signal and could do with some filtering, I tried a 4th order band pass but did not help much, am thinking about an integer FFT but not sure if the 8 will be fast enough even with the EAE, might try it with an Arduino first, and yes , the 348 does look a bit care worn but it is nearly 80 and has less added holes than some I have seen !
All in all been a lot of fun
Dave H
Although I passed the Radio Amatur theory exam in 1965 I never actually got my licence ( ticket) as I did not manage the then obligatory, for the UK, 12 word per minuet Morse. Listening to the ham band for the first time in 45 years or so I found that my ears could read the "CQ" and "DE" but nothing else . Could I have another go at leaning morse ? and why not use the Lab 8 to try and decode and rather than use a modern receiver how about resurrecting my BC348 communications receiver at the same time, again unused for 45 years or so.
This is what started this project and alone the way has been added a 1960's Solatron valve oscilloscope, why do my projects always grow arms and legs ?
We have
"short" long wire antenna "tree to shed", 9:1 ballam, 1930's BC348 -R valve ( tube) receiver, 1970's Brookdeal AC amplifier ( that's the box with the meter ), bread boarded charge pump and comparator to demodulate the AF ( that's the spaghetti sitting on the Brookdeal ), 1960's Solatron valve dual beam scope ( powered by the variac as I'm still not ready to give it full line voltage), the Lab 8/E.
Iv ended up using most the Lab8's extra laboratory peripherals, I/P is one a bit on the DR8-EA digital I/O, the DK8-ES real time clock does the mark and space timing, and the VC8-E displays this on the Tek 611 .
The A/D converter is used with the 4 front panel pots to input dot/dash and space discriminator thresholds.
I cheated a little bit with the software by writing the source on the " console" PC using notepad and initially uploading this to the 8 and running Pal8 under OS8 to assemble, then debug using ODT. I had forgotten how slow this could be so after the 3rd or 4th iteration I changed to using PALBAR and just transferring the binary, MUCH faster.
The actual decode is still fairly error prone and there is a good deal of "driving" involved, the weakest bit is the CW demod, needs a very good signal and could do with some filtering, I tried a 4th order band pass but did not help much, am thinking about an integer FFT but not sure if the 8 will be fast enough even with the EAE, might try it with an Arduino first, and yes , the 348 does look a bit care worn but it is nearly 80 and has less added holes than some I have seen !
All in all been a lot of fun
Dave H
