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2000-03-01 by telepath@tiac.net
Finished putting together my first MOTM module, the 120 Sub-Octave Multiplexer and power supply. Input A works fine, no problems. Input B doesn't seem to work in Cross Mode. I've checked the wires to the jack and there is continuity to the board. Since Input B doesn't work when in Cross Mode I'm wondering if anyone has any advice on further troubleshooting this problem. Telepathic regards, fRED
2000-03-01 by jwbarlow@aol.com
It's way too early for me to think about this, but you may need to use two "different" sound sources (one in each input) to get the cross product thing working (it does have the word "product" in there) -- others will be able to help you more here. Off to work -- with more thoughts on the PBX patching thing (I think Vosh got my idea). JB In a message dated 3/1/2000 7:50:21 AM, telepath@... writes:
>Finished putting together my first MOTM module, the 120 Sub-Octave >Multiplexer and power supply. > >Input A works fine, no problems. > >Input B doesn't seem to work in Cross Mode. I've checked the wires to >the >jack and there is continuity to the board. > >Since Input B doesn't work when in Cross Mode I'm wondering if anyone has >any advice on further troubleshooting this problem. >
2000-03-01 by Dave Bradley
If you put an audio signal into the B input and turn up the input knob, can you hear it at the output? Dave Bradley Principal Software Engineer Engineering Animation, Inc. daveb@...
> From: telepath@... > > Finished putting together my first MOTM module, the 120 Sub-Octave > Multiplexer and power supply. > > Input A works fine, no problems. > > Input B doesn't seem to work in Cross Mode. I've checked the wires to the > jack and there is continuity to the board. > > Since Input B doesn't work when in Cross Mode I'm wondering if anyone has > any advice on further troubleshooting this problem.
2000-03-01 by telepath@tiac.net
>From: "Dave Bradley" <daveb@...> > >If you put an audio signal into the B input and turn up the input knob, can >you hear it at the output? No, I can't.
> >Dave Bradley >Principal Software Engineer >Engineering Animation, Inc. >daveb@... > >> From: telepath@... >> >> Finished putting together my first MOTM module, the 120 Sub-Octave >> Multiplexer and power supply. >> >> Input A works fine, no problems. >> >> Input B doesn't seem to work in Cross Mode. I've checked the wires to the >> jack and there is continuity to the board. >> >> Since Input B doesn't work when in Cross Mode I'm wondering if anyone has >> any advice on further troubleshooting this problem. > > >------------------------------------------------------------------------ >Why wait for a credit decision? Get one instantly! Apply for >the Capital One 9.9% Fixed APR Visa Platinum! >http://click.egroups.com/1/1895/2/_/529958/_/951924206/ >------------------------------------------------------------------------
2000-03-01 by Dave Bradley
I don't have a schematic here at work, so my instructions may be a bit fuzzy. Also, I don't know your technical level, so I apologise if I inadvertantly insult you... Can you read a schematic well enough to find the opamp (triangle symbol with inputs marked + and -) that the B input feeds? If so, you want to listen to the output pin of the opamp to see if there is signal there. There will be 2 amps on the same chip, so the output pin will probably be either pin 1 or pin 7. The easiest thing to do for me is to take a spare jack and solder a couple of wires to it. Tack the ground wire to ground someplace (another jack's ground is convenient), plug some headphones in and power the module up. Then VERY CAREFULLY touch the hot wire to the correct opamp output pin and listen for signal. Don't touch anything else! If you have a signal there, we'll have to dig further. I suspect you won't. If you don't have a signal, then something is messed up in your input circuit. It could be a short in the coax cable, or a bad opamp chip. If you have a multimeter, desolder the hot wire of the B input from the circuit board, unplug the B input jack, and test for resistance between the hot and ground wires of the B input coax. I have had shorts occur there. Dave Bradley Principal Software Engineer Engineering Animation, Inc. daveb@...
> > From: telepath@... > > >From: "Dave Bradley" <daveb@...> > > > >If you put an audio signal into the B input and turn up the > input knob, can > >you hear it at the output? > > No, I can't. > > > > >Dave Bradley > >Principal Software Engineer > >Engineering Animation, Inc. > >daveb@... > > > >> From: telepath@... > >> > >> Finished putting together my first MOTM module, the 120 Sub-Octave > >> Multiplexer and power supply. > >> > >> Input A works fine, no problems. > >> > >> Input B doesn't seem to work in Cross Mode. I've checked the > wires to the > >> jack and there is continuity to the board. > >> > >> Since Input B doesn't work when in Cross Mode I'm wondering if > anyone has > >> any advice on further troubleshooting this problem. > > > > > >------------------------------------------------------------------------ > >Why wait for a credit decision? Get one instantly! Apply for > >the Capital One 9.9% Fixed APR Visa Platinum! > >http://click.egroups.com/1/1895/2/_/529958/_/951924206/ > >------------------------------------------------------------------------ > > > > ------------------------------------------------------------------------ > Why wait for a credit decision? Get one instantly! Apply for > the Capital One 9.9% Fixed APR Visa Platinum! > http://click.egroups.com/1/1895/2/_/529958/_/951926918/ > ------------------------------------------------------------------------ > >
2000-03-02 by Paul Schreiber
Err...read the manual :) Cross mode requires TWO inputs, IN A and IN B. Paul S. ----- Original Message -----
From: <telepath@...> To: <motm@onelist.com> Sent: Wednesday, March 01, 2000 8:47 AM Subject: [motm] MOTM-120 Troubleshooting > From: telepath@... > > Finished putting together my first MOTM module, the 120 Sub-Octave > Multiplexer and power supply. > > Input A works fine, no problems. > > Input B doesn't seem to work in Cross Mode. I've checked the wires to the > jack and there is continuity to the board. > > Since Input B doesn't work when in Cross Mode I'm wondering if anyone has > any advice on further troubleshooting this problem. > > Telepathic regards, > fRED > > > > ------------------------------------------------------------------------ > GET A NEXTCARD VISA, in 30 seconds! Get rates as low as 2.9% > Intro or 9.9% Fixed APR and no hidden fees. Apply NOW! > http://click.egroups.com/1/915/2/_/529958/_/951921972/ > ------------------------------------------------------------------------ > >
2000-03-02 by telepath@tiac.net
Yes, I know this and I've tried this and still can't get it going. By the way I read the manual ;) fRED
>From: "Paul Schreiber" <synth1@...> > >Err...read the manual :) > >Cross mode requires TWO inputs, IN A and IN B. > >Paul S. > >----- Original Message ----- >From: <telepath@...> >To: <motm@onelist.com> >Sent: Wednesday, March 01, 2000 8:47 AM >Subject: [motm] MOTM-120 Troubleshooting > > >> From: telepath@... >> >> Finished putting together my first MOTM module, the 120 Sub-Octave >> Multiplexer and power supply. >> >> Input A works fine, no problems. >> >> Input B doesn't seem to work in Cross Mode. I've checked the wires to the >> jack and there is continuity to the board. >> >> Since Input B doesn't work when in Cross Mode I'm wondering if anyone has >> any advice on further troubleshooting this problem. >> >> Telepathic regards, >> fRED >> >> >> >> ------------------------------------------------------------------------ >> GET A NEXTCARD VISA, in 30 seconds! Get rates as low as 2.9% >> Intro or 9.9% Fixed APR and no hidden fees. Apply NOW! >> http://click.egroups.com/1/915/2/_/529958/_/951921972/ >> ------------------------------------------------------------------------ >> >> > > >------------------------------------------------------------------------ >GET A NEXTCARD VISA, in 30 seconds! Get rates >as low as 0.0% Intro APR and no hidden fees. >Apply NOW! >http://click.egroups.com/1/975/2/_/529958/_/951970919/ >------------------------------------------------------------------------
2000-03-02 by Paul & Alleyne
hello all hello fRed as always seems to be the case when i build something (tho not with motm so far, touch wood), it's always something bloody obvious on the board if you can, you could try scanning in the board, and putting it on a url, that way those of us who can help can look over your board for anything back to front / stuffed in the wrong hole seems like a good idea..? wait - you haven't got a scanner have you..? cheers paul b
2000-03-02 by Dave Bradley
I looked at the schematic last night, and need to revise some of my comments below. There is only one summing amp setup in the system, so if you are getting any sound at all out of the output, it's not a bad opamp. I suspect you either have the toggle switch for the B side wired wrong, or you have a short in the B input coax cable as I mentioned previously. Double check your switch wiring! There's not much else that could be wrong. Of course, if you can use the switch to get the normal sound at the output, but the square sound doesn't work, then probably the comparator LM311 is bad. Dave Bradley Principal Software Engineer Engineering Animation, Inc. daveb@...
> -----Original Message----- > From: Dave Bradley [mailto:daveb@...] > Sent: Wednesday, March 01, 2000 10:35 AM > To: motm@onelist.com > Subject: RE: [motm] MOTM-120 Troubleshooting > > > From: "Dave Bradley" <daveb@...> > > I don't have a schematic here at work, so my instructions may be a bit > fuzzy. Also, I don't know your technical level, so I apologise if I > inadvertantly insult you... > > Can you read a schematic well enough to find the opamp (triangle > symbol with > inputs marked + and -) that the B input feeds? If so, you want to > listen to > the output pin of the opamp to see if there is signal there. > There will be 2 > amps on the same chip, so the output pin will probably be either pin 1 or > pin 7. The easiest thing to do for me is to take a spare jack and solder a > couple of wires to it. Tack the ground wire to ground someplace (another > jack's ground is convenient), plug some headphones in and power the module > up. Then VERY CAREFULLY touch the hot wire to the correct opamp output pin > and listen for signal. Don't touch anything else! > > If you have a signal there, we'll have to dig further. I suspect > you won't. > If you don't have a signal, then something is messed up in your input > circuit. It could be a short in the coax cable, or a bad opamp chip. > > If you have a multimeter, desolder the hot wire of the B input from the > circuit board, unplug the B input jack, and test for resistance > between the > hot and ground wires of the B input coax. I have had shorts occur there. > > Dave Bradley > Principal Software Engineer > Engineering Animation, Inc. > daveb@... > > > > > From: telepath@... > > > > >From: "Dave Bradley" <daveb@...> > > > > > >If you put an audio signal into the B input and turn up the > > input knob, can > > >you hear it at the output? > > > > No, I can't. > > > > > > > >Dave Bradley > > >Principal Software Engineer > > >Engineering Animation, Inc. > > >daveb@... > > > > > >> From: telepath@... > > >> > > >> Finished putting together my first MOTM module, the 120 Sub-Octave > > >> Multiplexer and power supply. > > >> > > >> Input A works fine, no problems. > > >> > > >> Input B doesn't seem to work in Cross Mode. I've checked the > > wires to the > > >> jack and there is continuity to the board. > > >> > > >> Since Input B doesn't work when in Cross Mode I'm wondering if > > anyone has > > >> any advice on further troubleshooting this problem. > > > >
2000-03-02 by telepath@tiac.net
Telepathic Gratitude to all the helpful suggestions about what may have been wrong with my 120 module. Turns out it was the coax cable from In B to the board, which had a short in it as one of you suggested. Now it works like a charm! :) Telepathic regards, fRED