Resistance checks on RF board page 38
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Good evening all, just making my way through the K2 build and had was wondering about some resistance check results. On R115 and U1 pins 4,9,10,28 I am getting readings in the range of 3.9 mega ohms to 5.4 mega ohms. The results sheet advise of results in and around 20k. In the past I have found that the measured amount was somewhat close to the expected manual. To me it just seems a bit high when you are to see greater than 20K and the measured amount is in the Mega ohms....is this normal?The last measurement question I have is for R1 and R2. I have to see 1mega ohm or more and my Fluke is just reading OL....is this what I am looking for?The only "normal" reading in this check out to me is U1 pin 1 which comes in at 4.85K Thanks for your timeMikehttp://elecraftk2.blogspot.ca/
Exact readings I am gettingR115 9.57mega ohmsU1Pin 4 3.9 mega ohmsPin 9 4.8 " "Pin 10 4.7 " "Pin 28 5.4 " " ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: Resistance checks on RF board page 38
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Mike.
Try reversing your DMM probes and see if that makes any difference. My immediate reaction is to say that you may have soldering connections that are not good. Inspect the soldering with a critical eye. Any joints where the solder did not flow completely out onto the solder pad are suspect, and may be a result of too cold an iron or not enough dwell time on the connection. You should see the solder flow out onto both the pad and the component lead to almost an invisible edge line in 3 seconds. If it does not do that, then the iron is too cold. You will not hurt modern components with a soldering temperature of 759 degF for a time of 5 seconds or less. 73, Don W3FPR On 5/10/2013 9:02 PM, Mike Weir wrote: > Good evening all, just making my way through the K2 build and had was wondering about some resistance check results. On R115 and U1 pins 4,9,10,28 I am getting readings in the range of 3.9 mega ohms to 5.4 mega ohms. The results sheet advise of results in and around 20k. In the past I have found that the measured amount was somewhat close to the expected manual. To me it just seems a bit high when you are to see greater than 20K and the measured amount is in the Mega ohms....is this normal?The last measurement question I have is for R1 and R2. I have to see 1mega ohm or more and my Fluke is just reading OL....is this what I am looking for?The only "normal" reading in this check out to me is U1 pin 1 which comes in at 4.85K Thanks for your timeMikehttp://elecraftk2.blogspot.ca/ > > Exact readings I am gettingR115 9.57mega ohmsU1Pin 4 3.9 mega ohmsPin 9 4.8 " "Pin 10 4.7 " "Pin 28 5.4 " " > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Good evening Don,
Here is what I have done, 1. I have tried reversing the leads on the DMM and the readings for lets say U1 pin 4 to ground went from 3.9 mega ohms to 2.9 mega ohms. so not really the reading I am looking for. 2. I heated up all the solder connections on the board and added solder where needed. I am using the WES51 iron turned all the way up. Here is one of my trouble shooting paths I did for U1 pin 4. 1. From U1 pin 4 to K13 pin 10.....result .02 ohms....a good result 2. From U1 pin 4 to K13 pin 1.......result 239.8 ohms a good result as this is the coil of K13 3. From U1 pin 4 to K9 pin 1.........result 239.8 ohms a good result as again this is coil of K13 only. 4. From U1 pin 4 to K9 pin 10.......result 480.6 ohms a good result reading coils from K13 and K9. 5. From U1 pin 4 to U1 pin 13.......result 480.6 ohms a good result again reading both coils K13 and K9 Note C82, C57 and C208 are in this circuit but not as yet installed. Now I go from ground to Pin 4 and am reading in the Mega ohms. And no matter which ground point I go to I get the same high ohm reading. As for R1 and R2 1. On R1 going from bottom terminal (terminal above R2) to C1 top side and get reading of .02 ohms...this is good 2. From same position on R1 again to other side of C1 and get OL. 3. I then go from the same position on R1 again to ground and again get OL. Not sure where to go next Don. Mike VE3WDM |
Re: Resistance checks on RF board page 38
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Mike,
The place to go next is to continue onto page 39 of the manual. Note that for those values listed have a ">" symbol - which means 'greater than' (see page 22, top of the 2nd column). A reading in the Megohms range is definitely greater than 20k, so no problem. The same thing applies to the R1 and R2 readings - greater than 1 megohm can be an infinite reading, which apparently your meter indicates as "OL" (overload) - it should be the same thing as is displayed with the probes connected to nothing. Some meters show a "1" in the 1st digit position for an infinite resistance condition, others blink the display, and others indicate "OL" as yours does. Know how your meter responds to an infinite resistance (open leads) and also to zero ohms - and be aware of the meter range, especially if using auto-ranging. An old wise saying among the lab engineers I worked with was "Test Engineer, know your tools, and know when *not* to believe them" - refer to the manual for your tool if there is any question about what is being indicated, many are different in subtle ways. 73, Don W3FPR On 5/12/2013 5:14 PM, VE3WDM wrote: > Good evening Don, > Here is what I have done, > 1. I have tried reversing the leads on the DMM and the readings for lets say > U1 pin 4 to ground went from 3.9 mega ohms to 2.9 mega ohms. so not really > the reading I am looking for. > > 2. I heated up all the solder connections on the board and added solder > where needed. I am using the WES51 iron turned all the way up. > > Here is one of my trouble shooting paths I did for U1 pin 4. > 1. From U1 pin 4 to K13 pin 10.....result .02 ohms....a good result > 2. From U1 pin 4 to K13 pin 1.......result 239.8 ohms a good result as this > is the coil of K13 > 3. From U1 pin 4 to K9 pin 1.........result 239.8 ohms a good result as > again this is coil of K13 only. > 4. From U1 pin 4 to K9 pin 10.......result 480.6 ohms a good result > reading coils from K13 and K9. > 5. From U1 pin 4 to U1 pin 13.......result 480.6 ohms a good result again > reading both coils K13 and K9 > Note C82, C57 and C208 are in this circuit but not as yet installed. > > Now I go from ground to Pin 4 and am reading in the Mega ohms. And no matter > which ground point I go to I get the same high ohm reading. > > As for R1 and R2 > 1. On R1 going from bottom terminal (terminal above R2) to C1 top side and > get reading of .02 ohms...this is good > 2. From same position on R1 again to other side of C1 and get OL. > 3. I then go from the same position on R1 again to ground and again get OL. > > Not sure where to go next Don. > Mike > VE3WDM > > > > > -- > View this message in context: http://elecraft.365791.n2.nabble.com/Resistance-checks-on-RF-board-page-38-tp7573563p7573597.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by Don Wilhelm-4
Good evening Don, Thanks very much for the great new I just wanted to make sure all was well before I moved on to the next section.
Mike VE3WDM |
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In reply to this post by VE3WDM
The user book says 14vdc... I have a reg. power supply that does,15.000 vdc. Is that going to be a problem?
Phil Non judgement day is near On May 10, 2013, at 7:02 PM, Mike Weir <[hidden email]> wrote: > Good evening all, just making my way through the K2 build and had was wondering about some resistance check results. On R115 and U1 pins 4,9,10,28 I am getting readings in the range of 3.9 mega ohms to 5.4 mega ohms. The results sheet advise of results in and around 20k. In the past I have found that the measured amount was somewhat close to the expected manual. To me it just seems a bit high when you are to see greater than 20K and the measured amount is in the Mega ohms....is this normal?The last measurement question I have is for R1 and R2. I have to see 1mega ohm or more and my Fluke is just reading OL....is this what I am looking for?The only "normal" reading in this check out to me is U1 pin 1 which comes in at 4.85K Thanks for your timeMikehttp://elecraftk2.blogspot.ca/ > > Exact readings I am gettingR115 9.57mega ohmsU1Pin 4 3.9 mega ohmsPin 9 4.8 " "Pin 10 4.7 " "Pin 28 5.4 " " > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Phil,
Exceeding the specifications with any equipment is "at your own peril" with any equipment. Although I doubt that 15 volts will cause a problem with the KX1, the regulators will generate more heat than the design point predicts - and there may be other consequences. A few diodes in the power cable for that power source will drop the voltage down, or choose another supply. Some power supplies can be adjusted for output voltage, but I suspect you have a sealed power supply that was intended for a computer, so do what you have to to remain is spec. 73, Don W3FPR On 5/12/2013 7:24 PM, Philip Townsend Lontz wrote: > The user book says 14vdc... I have a reg. power supply that does,15.000 vdc. Is that going to be a problem? > Phil > > Non judgement day is near > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Thank you Don...
Non judgement day is near On May 12, 2013, at 5:41 PM, Don Wilhelm <[hidden email]> wrote: > Phil, > > Exceeding the specifications with any equipment is "at your own peril" with any equipment. > Although I doubt that 15 volts will cause a problem with the KX1, the regulators will generate more heat than the design point predicts - and there may be other consequences. > > A few diodes in the power cable for that power source will drop the voltage down, or choose another supply. Some power supplies can be adjusted for output voltage, but I suspect you have a sealed power supply that was intended for a computer, so do what you have to to remain is spec. > > 73, > Don W3FPR > > On 5/12/2013 7:24 PM, Philip Townsend Lontz wrote: >> The user book says 14vdc... I have a reg. power supply that does,15.000 vdc. Is that going to be a problem? >> Phil >> >> Non judgement day is near >> Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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The PS in question is a regulated ps from an AOR 7030 receiver. It's got a bit of ripple as well. Non adjustable but I may Change that. I don't want to stress the regulators in the KX1... So maybe another supply is in order... Might be easier.
Non judgement day is near On May 12, 2013, at 5:44 PM, Philip Townsend Lontz <[hidden email]> wrote: > Thank you Don... > > Non judgement day is near > > > > > On May 12, 2013, at 5:41 PM, Don Wilhelm <[hidden email]> wrote: > >> Phil, >> >> Exceeding the specifications with any equipment is "at your own peril" with any equipment. >> Although I doubt that 15 volts will cause a problem with the KX1, the regulators will generate more heat than the design point predicts - and there may be other consequences. >> >> A few diodes in the power cable for that power source will drop the voltage down, or choose another supply. Some power supplies can be adjusted for output voltage, but I suspect you have a sealed power supply that was intended for a computer, so do what you have to to remain is spec. >> >> 73, >> Don W3FPR >> >> On 5/12/2013 7:24 PM, Philip Townsend Lontz wrote: >>> The user book says 14vdc... I have a reg. power supply that does,15.000 vdc. Is that going to be a problem? >>> Phil >>> >>> Non judgement day is near > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by Phillip Lontz
HI,
KX3, I have played about with the two mike settings BIAS (on/off) and pgupdwn/ptt/off with a computer headset where the 3.5mm mike has a stereo plug and no joy. Noted it initially as got the PTT error message and TX stays open when plugged in. No amount of combinations of with VOX on/off and setting the mike options seems to make it work where pressing the PTT on the KX3 keys the mike (or VOX does). A stereo to mono adapter doesn't seem to help. Anyone had a similar problem and got a cure? The headset is identical to another I have as I wanted to get a second set (for second KX3) but the earlier one has a mono mike. I looked at chopping the cable and rewiring (The mike has a tiny + screw in it so I undid it just to see how it was wired) but I noted the wires are not the easy to solder type. 72 Dom M1KTA ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Hi Dom,
When I plug in the mic of my PC-headset I can operate the vox without any problem. MIC BTN=off and MIC BIAS=off... When I measure the mic connection with a standard 3.5 mm. stereo cable with two RCA plugs at the other end, I end up having no voltage on the tip of the 3.5 mm plug and 2.4 volts on the middle ring. That is the situation I'd expect it to be: These mics are usually wired for mic inputs of soundcards and they carry the bias supply voltage on the middle ring and the AF output comes from the tip. Switching on the MIC BIAS ads an audible noise on my monitor as does setting the MIC BTN either to PTT or to PTT UP.DN. Of course in the MIC BTN=off you have no PTT function on the plug available, so use of VOX is the only option to transmit. In fact the PTT function is off but the logic level stays high and that supplies the microphone with the necessary bias form the VPTTUPDN line that comes straight from the PIC U10 via a 1k resistor if I understand the schematic part 'KX3 Control Panel: Connectors' right. I don't know whether J8 in the drawing signifies the MIC connector but I doubt that for it does not have that extra ring on on the MH3 microphone plug for nothing. I looked through all drawings but could not find that connector. Maybe someone else can fill in the gaps...? 72/73, Peter - PA0PJE [hidden email] schreef: > HI, > > KX3, I have played about with the two mike settings BIAS (on/off) and > pgupdwn/ptt/off with a computer headset where the 3.5mm mike has a > stereo plug and no joy. Noted it initially as got the PTT error message > and TX stays open when plugged in. No amount of combinations of with VOX > on/off and setting the mike options seems to make it work where pressing > the PTT on the KX3 keys the mike (or VOX does). > > A stereo to mono adapter doesn't seem to help. > > Anyone had a similar problem and got a cure? > > The headset is identical to another I have as I wanted to get a second > set (for second KX3) but the earlier one has a mono mike. > > I looked at chopping the cable and rewiring (The mike has a tiny + screw > in it so I undid it just to see how it was wired) but I noted the wires > are not the easy to solder type. > > 72 > Dom > M1KTA > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: KX3 PC Headset Stereo mike
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Thanks Peter,
I will play with a set of RCA terminated leads in a similar way and measure voltages. It could be that the tolerance in the position of the 1st and 2nd ring on the mike plug are slightly different (was a cheap headset), magnified there is about a 0.2mm difference between the one on the headset and the audio plug or that on a typical stereo plug grabbed from the junk box. I have a feeling it might be better to build a unit that uses a 4 connector plug and plug that into the KX3 and the the headset into that, and then any hand held or foot PTT? What is odd as with a mono mike (both headsets are the same just one has a mono mike plug) I had to do nothing in the KX3 menus and and both VOX and PTT on the KX3 operated without having to alter either. I think the drawings are 99.99% complete but missing a few minor things especially the details for the inter connections as you have discovered as well. 72 Dom M1KTA On 13/05/13 15:13, Peter Eijlander (PA0PJE) wrote: > Hi Dom, > > When I plug in the mic of my PC-headset I can operate the vox without > any problem. MIC BTN=off and MIC BIAS=off... > > When I measure the mic connection with a standard 3.5 mm. stereo cable > with two RCA plugs at the other end, I end up having no voltage on the > tip of the 3.5 mm plug and 2.4 volts on the middle ring. That is the > situation I'd expect it to be: These mics are usually wired for mic > inputs of soundcards and they carry the bias supply voltage on the > middle ring and the AF output comes from the tip. > > Switching on the MIC BIAS ads an audible noise on my monitor as does > setting the MIC BTN either to PTT or to PTT UP.DN. > > Of course in the MIC BTN=off you have no PTT function on the plug > available, so use of VOX is the only option to transmit. > > In fact the PTT function is off but the logic level stays high and > that supplies the microphone with the necessary bias form the VPTTUPDN > line that comes straight from the PIC U10 via a 1k resistor if I > understand the schematic part 'KX3 Control Panel: Connectors' right. > > I don't know whether J8 in the drawing signifies the MIC connector but > I doubt that for it does not have that extra ring on on the MH3 > microphone plug for nothing. I looked through all drawings but could > not find that connector. > > Maybe someone else can fill in the gaps...? > > 72/73, > Peter - PA0PJE > > [hidden email] schreef: >> HI, >> >> KX3, I have played about with the two mike settings BIAS (on/off) and >> pgupdwn/ptt/off with a computer headset where the 3.5mm mike has a >> stereo plug and no joy. Noted it initially as got the PTT error message >> and TX stays open when plugged in. No amount of combinations of with VOX >> on/off and setting the mike options seems to make it work where pressing >> the PTT on the KX3 keys the mike (or VOX does). >> >> A stereo to mono adapter doesn't seem to help. >> >> Anyone had a similar problem and got a cure? >> >> The headset is identical to another I have as I wanted to get a second >> set (for second KX3) but the earlier one has a mono mike. >> >> I looked at chopping the cable and rewiring (The mike has a tiny + screw >> in it so I undid it just to see how it was wired) but I noted the wires >> are not the easy to solder type. >> >> 72 >> Dom >> M1KTA >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[hidden email] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by pa0pje
Peter,
Bias is "added" to the tip via menu. The voltage you read on the 1st ring is the pull-up for the PTT & UP/Down buttons. See the schematic for the MH3 microphone ( http://www.elecraft.com/manual/MH3%20Rev%20A.pdf ). It does show the connections to the mic plug. I can not find the Mic jack on the KX3 schematics. I used the MH3 schematic to make an adapter to interface my K3 microphones in case I need my KX3 to back-up my K3 & KPA500. 73 George AI4VZ -----Original Message----- From: Peter Eijlander (PA0PJE) Hi Dom, When I measure the mic connection with a standard 3.5 mm. stereo cable with two RCA plugs at the other end, I end up having no voltage on the tip of the 3.5 mm plug and 2.4 volts on the middle ring. That is the situation I'd expect it to be: These mics are usually wired for mic inputs of soundcards and they carry the bias supply voltage on the middle ring and the AF output comes from the tip. . . . ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Thanks George, I was looking for that schematic but probably didn't look
hard enough:-) 72/73, Peter - PA0PJE GDanner schreef: > Peter, > Bias is "added" to the tip via menu. > > The voltage you read on the 1st ring is the pull-up for the PTT & UP/Down > buttons. > > See the schematic for the MH3 microphone ( > http://www.elecraft.com/manual/MH3%20Rev%20A.pdf ). > It does show the connections to the mic plug. > I can not find the Mic jack on the KX3 schematics. > > I used the MH3 schematic to make an adapter to interface my K3 microphones > in case I need my KX3 to back-up my K3 & KPA500. > > 73 > George > AI4VZ > > > > -----Original Message----- > From: Peter Eijlander (PA0PJE) > Hi Dom, > > When I measure the mic connection with a standard 3.5 mm. stereo cable > with two RCA plugs at the other end, I end up having no voltage on the > tip of the 3.5 mm plug and 2.4 volts on the middle ring. That is the > situation I'd expect it to be: These mics are usually wired for mic > inputs of soundcards and they carry the bias supply voltage on the > middle ring and the AF output comes from the tip. > > . . . > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by George Danner
You're right, Iain.
Measured it on my headset and indeed tip and ring are joined. iain macdonnell - N6ML schreef: > It seems that most PC headsets connect the tip and ring together, so > they can take bias from either, and that connecting the tip and ring ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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