Re: ANN: mt63lx version 0.5

[chuck gelm <chuck@gelm.net>]

Hi, Dave:

Thanks.

I have added the linux-hams list back into the address as I still
have unanswered concerns.

Dave Platt wrote:
>>"...
>>The MT63 modem is made for single side band operation. The audio
>>generated by the modem (sound card output) is applied to the SSB
>>modulator. On the receiver side, the output of the SSB demodulator
>>is put into the sound card input. ..."
>>
>>  Am I correct in assuming that 'SSB modulator' is not SSB microphone
>>input and 'SSB demodulator' is not SSB speaker output.
> 
> 
> No, I think you are not correct.
> 
> Most modulations of this general sort can work if you feed the audio
> in through the mic input, and take the output from the speaker jack.
> You may need to add a resistive pad (a simple volume control or
> attenuator) to make sure that you don't overdrive the mic input and
> cause distortion, and you might need to add a similar pad in the other
> direction so that your rig's speaker output doesn't overdrive your
> laptop's line or mic input.
> 
> If your rig has an auxiliary-audio I/O jack (e.g. for connection to a
> TNC) this is often a better choice, as the voltage levels expected on
> this jack may be closer to what a PC sound card generates and expects.
> 
> Using a PC-to-rig adapter which has a transformer isolation for each
> audio line, and an optoisolator for PTT, is usually a good idea - it
> prevents ground loops, can help keep RF out of the PC and keep PC
> switching noise out of the rig.
> 
> 
>>I didn't see any mention of kernel version or CPU speed or tools or...
> 
> 
> I've run PSK31, and the MFSK codec in the gMFSK program, successfully
> on a Pentium 233 MMX laptop.

Dave:

  You make no mention of 'MT63' in your response.

I have a BuxComm GL?-V which copies PSK31 and other emissions,
although I have yet to have had anyone acknowledge my
transmission attempts.  I assume that this device will
provide acceptable voltages to my SSB rig (Kenwood TS-50).
This device and the accompanying software seems to receive
fine on a 266 MHz Pentium II computer.  I assume that the
CPU speed is less important in transmiting than it is in
receiving.

  Perhaps 'PSK31', 'MFSK', or 'gMFSK' implies ,MT63'.
However I do not recall them being mentioned in the original message
or attachment.

I am still missing software requirements;
kernel version, gcc, utilities, tools, ...

  Is 'MT63' a development project or is it really ready for
'user' deployment?  i.e. Is it 'alpha', 'beta', or
stable release?

Regards, Chuck nc8q

Eschew obfuscation! Espouse elucidation!