> My L1 82 mH inductor has a DC resistance of 62 ohms. This is quite different > from the 180 ohm version used in the mod. Would a series resistor be desired > as Fred indicates in the message below? I have 100 ohm, 120 ohm, and 150 ohm > resistors on hand. Where is this resistor installed between U10 pin 7 and the > inductor or between the inductor and C33?
> What type of capacitor would be best suited for this mod? My junk box only has > 1 uF 100 V 5% metallized polyester or 2.2 uF 16 V 10% dipped tantalum > capacitors. The polyester caps are rather large. A couple of the 2.2s in > series would be 1.1 uF. Darrell, I did the TF3MA sidetone mod some months ago on my K2 serial #2198 and I am very pleased with it. See my comments on http://www.ac6rm.net/mailarchive/html/elecraft-list/2006-12/msg01043.html where I wrote that "This mod really works wonders with the sidetone quality of the K2". I had done the sidetone upgrade to the 3000+ model previously, but this latest change still was very worthwhile doing. You should add series resistance to the inductor. If I understand your question right, the order, L+R or R+L, doesn't make any difference. I would try the 120 ohm resistor giving you a total of 120+62 = 182 ohms. Maybe the size I would probably have tried with the series combination of two 2.2 uF tantalum capacitors in order to avoid putting the large 1 uF capacitor in there. 73 Sverre LA3ZA Unofficial Guide to K2 Modifications http://www.qslnet.de/member/la3za/K2/mod.html -- I am using the free version of SPAMfighter for private users. It has removed 7471 spam emails to date. Paying users do not have this message in their emails. Get the free SPAMfighter here: http://www.spamfighter.com/len _______________________________________________ Elecraft mailing list Post to: [email protected] 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
