OPT1 low volume
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I'm still trying to figure out why signals drop when I switch in OPT1
on my newly-built SSB board for my K2/100. The static goes way down, but do do the voices! Last weekend I discovered rfc2 shorting out to they can of crystal X7. When I rewound it that helped some. Today I rewound T2 and that didn't make any difference at all. I've been around once with Gary, and I think all the obvious things are right. The crystal cans aren't shorted to ground, the caps are the right values and aren't shorted by DC either, the diodes are in the right way and the voltage checks on the switching network are fine. Gary says there should be a "small but progressive" signal loss through the SSB filter. To check this, I tuned to the birdie at the bottom of 40 meters, and dragged out the scope. I set in on a 2mv scale with a 1ms sweep (slow) and used the measuring cursors to take an average amplitude. I did AC coupling with a 1X probe (so may have been loading things down some). Then I shoved a 3 inch leftover component lead into the probe clip so I could poke around in the small places. Here are the numbers, from input to output: P2 -> T1(2) -> T2(4) -> X1 == ~ 1.75mv before X2 1.28mv before X3 1.28mv before X4 1.28mv before X5 1.28mv before X6 1.20mv before X7 1.20mv T2(3) 1.20mv T2(1) --> all the way out to P3 ~1.68mv I can go around again with Gary -- but before the weekend goes and before I tear too much working stuff up, thought I'd throw it out to you guys to see if there is anything obviously wrong with these numbers or the way I acquired them. Thanks, -- Ward _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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I'm not quite sure what you mean about the "crystal cans"
not being shorted to ground. They are supposed to be grounded. 73, Doug W6JD ----- Original Message ----- From: "Ward Willats" <[hidden email]> To: <[hidden email]> Sent: Saturday, October 02, 2004 3:30 PM Subject: [Elecraft] OPT1 low volume > I'm still trying to figure out why signals drop when I switch in OPT1 > on my newly-built SSB board for my K2/100. The static goes way down, > but do do the voices! > > Last weekend I discovered rfc2 shorting out to they can of crystal > X7. When I rewound it that helped some. > > Today I rewound T2 and that didn't make any difference at all. > > I've been around once with Gary, and I think all the obvious things > are right. The crystal cans aren't shorted to ground, the caps are > the right values and aren't shorted by DC either, the diodes are in > the right way and the voltage checks on the switching network are > fine. > > Gary says there should be a "small but progressive" signal loss > through the SSB filter. To check this, I tuned to the birdie at the > bottom of 40 meters, and dragged out the scope. > > I set in on a 2mv scale with a 1ms sweep (slow) and used the > measuring cursors to take an average amplitude. I did AC coupling > with a 1X probe (so may have been loading things down some). Then I > shoved a 3 inch leftover component lead into the probe clip so I > could poke around in the small places. > > Here are the numbers, from input to output: > > P2 -> T1(2) -> T2(4) -> X1 == ~ 1.75mv > > before X2 1.28mv > before X3 1.28mv > before X4 1.28mv > before X5 1.28mv > before X6 1.20mv > before X7 1.20mv > > T2(3) 1.20mv > T2(1) --> all the way out to P3 ~1.68mv > > I can go around again with Gary -- but before the weekend goes and > before I tear too much working stuff up, thought I'd throw it out to > you guys to see if there is anything obviously wrong with these > numbers or the way I acquired them. > > Thanks, > > -- Ward > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Ward Willats-3
You said the "cans aren't shorted" to ground, or did you mean the signal
path isn't shorted? It's amazingly easy to use a tad too much solder on one of the crystal lead pads, and it'll form enough of a bump under the can to short the signal path to the can and ground. Usually that kills the output completely, but a higher resistance short is also possible that would simply bring the signal way down. Check the resistance at each crystal pin to ground and make sure the resistance is at least many megohms (should be an open circuit). Ron AC7AC -----Original Message----- I'm still trying to figure out why signals drop when I switch in OPT1 on my newly-built SSB board for my K2/100. The static goes way down, but do do the voices! Last weekend I discovered rfc2 shorting out to they can of crystal X7. When I rewound it that helped some. Today I rewound T2 and that didn't make any difference at all. I've been around once with Gary, and I think all the obvious things are right. The crystal cans aren't shorted to ground, the caps are the right values and aren't shorted by DC either, the diodes are in the right way and the voltage checks on the switching network are fine... -- Ward _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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>You said the "cans aren't shorted" to ground, or did you mean the signal
>path isn't shorted? Ooops. Yes, I mis-wrote. The signal path is not shorted. The path from the crystal PINS to ground is absolutely open in all cases. -- Ward _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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After finishing #4439, I'm getting low on solder. I've always used Ersin Multicore (now part of Loctite), and got my last pound from Digi-Key, which doesn't stock it anymore. Searching the archive, it seems that it's pretty hard to find a distributor for Multicore these days. A bit of web searching found a supplier, with reasonable prices and no minimum order. They seem to carry most of the Multicore wire solder:
https://rshughes.com/catalog/129900.html They have the .020 63/37 WRAP3 fluxed stuff (MM00979) on which a group buy was done last spring, for $9.50. WRAP3 appears to be an activated rosin flux. I've been pretty happy with their Crystal 400 2% flux (MM01054), so I'm ordering a spool of that, for the same price. Info on the Crystal 400 flux is here: http://www.prime-electronics.com.au/datasheets/Multicore/Solder%20Wire/No%20Clean/Crystal%20400,%20500,%20502,%20505%20&%20511.pdf _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Ward Willats-3
Ward,
>From your numbers, it does not seem that you have any excessive loss through the xtal filter. First, check soldering, then check soldering, and when you have completed that, check the soldering. That is the most common cause of problems. It may simply be that your BFO frequencies are not correct. The values in the KSB2 manual are only starting points - if your manual is older (for the 2.0 kHz bandwidth), and you have installed the capacitors for the 2.2 (2.3) or 2.5 kHz bandwidth, you can expect that the initial BFO frequencies will not be correct. Check out my website www.qsl.net/w3fpr article on K2 Dial Calibration for the long story - or skip right to that article's Step 3 - CAL FIL for details on how to properly align the BFOs to give you the proper demodulated audio range. 73, Don W3FPR ----- Original Message ----- > I'm still trying to figure out why signals drop when I switch in OPT1 on > my newly-built SSB board for my K2/100. The static goes way down, but do > do the voices! > > Last weekend I discovered rfc2 shorting out to they can of crystal X7. > When I rewound it that helped some. > > Today I rewound T2 and that didn't make any difference at all. > > I've been around once with Gary, and I think all the obvious things are > right. The crystal cans aren't shorted to ground, the caps are the right > values and aren't shorted by DC either, the diodes are in the right way > and the voltage checks on the switching network are fine. > > Gary says there should be a "small but progressive" signal loss through > the SSB filter. To check this, I tuned to the birdie at the bottom of 40 > meters, and dragged out the scope. > > I set in on a 2mv scale with a 1ms sweep (slow) and used the measuring > cursors to take an average amplitude. I did AC coupling with a 1X probe > (so may have been loading things down some). Then I shoved a 3 inch > leftover component lead into the probe clip so I could poke around in the > small places. > > Here are the numbers, from input to output: > > P2 -> T1(2) -> T2(4) -> X1 == ~ 1.75mv > > before X2 1.28mv > before X3 1.28mv > before X4 1.28mv > before X5 1.28mv > before X6 1.20mv > before X7 1.20mv > > T2(3) 1.20mv > T2(1) --> all the way out to P3 ~1.68mv > > I can go around again with Gary -- but before the weekend goes and before > I tear too much working stuff up, thought I'd throw it out to you guys to > see if there is anything obviously wrong with these numbers or the way I > acquired them. > _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Multicore solder availability
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In reply to this post by Mike S-8
I bought a pound about 6 months ago from a local distributor who does not
stock it anymore. It was one of the last rolls they had. I also bought a pound of Kester "44". I found the Multicore (says Made in USA) had a peculiar smell and also didn't seem nearly as good as the old stuff I still have a bit of! I haven't bought Kester in over 30 years and I must say the newest "44" stuff is very excellent! After this experiance, I don't think I'll bother trying to find the Multicore anymore as it's performance (new roll) was somewhat disappointing compared with the old stuff. Has anone else had this happen or is it a fluke? 73, Sandy W5TVW ----- Original Message ----- From: "Mike S" <[hidden email]> To: <[hidden email]> Sent: Saturday, October 02, 2004 8:34 PM Subject: [Elecraft] Multicore solder availability | After finishing #4439, I'm getting low on solder. I've always used Ersin Multicore (now part of Loctite), and got my last pound from Digi-Key, which doesn't stock it anymore. Searching the archive, it seems that it's pretty hard to find a distributor for Multicore these days. A bit of web searching found a supplier, with reasonable prices and no minimum order. They seem to carry most of the Multicore wire solder: | | https://rshughes.com/catalog/129900.html | | They have the .020 63/37 WRAP3 fluxed stuff (MM00979) on which a group buy was done last spring, for $9.50. WRAP3 appears to be an activated rosin flux. I've been pretty happy with their Crystal 400 2% flux (MM01054), so I'm ordering a spool of that, for the same price. | | Info on the Crystal 400 flux is here: http://www.prime-electronics.com.au/datasheets/Multicore/Solder%20Wire/No%20Clean/Crystal%20400,%20500,%20502,%20505%20&%20511.pdf | | _______________________________________________ | Elecraft mailing list | Post to: [hidden email] | You must be a subscriber to post to the list. | Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft | Help: http://mailman.qth.net/subscribers.htm | Elecraft web page: http://www.elecraft.com | | _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Multicore solder availability
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On Sun, Oct 03, 2004 at 08:11:34PM -0500, Sandy W5TVW wrote:
> I bought a pound about 6 months ago from a local distributor who does not > stock it anymore. It was one of the last rolls they had. I also bought a pound of > Kester "44". I found the Multicore (says Made in USA) had a peculiar smell > and also didn't seem nearly as good as the old stuff I still have a bit of! > > I haven't bought Kester in over 30 years and I must say the newest "44" > stuff is very excellent! After this experiance, I don't think I'll bother > trying to find the Multicore anymore as it's performance (new roll) > was somewhat disappointing compared with the old stuff. > > Has anone else had this happen or is it a fluke? Multicore (as well as several other manufacturers) has a variety of fluxes available. I suspect that is the difference. I bought a roll of Multicore solder with "no-clean" flux a few years ago and am quite happy with it. All I could find was .035, so I later bought a roll of Kester "44" in .020 dia for the small stuff. Bob, N7XY _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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