Tom,
Your project brings back alot of memories. I do have a good assortment of low value mica caps (same physical size as used across helicals). Lots of 2pf on up to at least 10pf. I used many of the caps to "Pad" coils in "Sensicon" and Motrac rigs, in years gone by. I enjoy Motrac Stuff.......Still using a Motrac rpt.(100w tube PA). Let me know off line if you require any caps......Merry Christmas! Tim W7TRH / AFA0TP Wa. ----- Original Message ----- From: "wb6dgn" <[email protected]> To: [email protected] Sent: Wednesday, December 16, 2009 4:17:07 PM GMT -08:00 US/Canada Pacific Subject: [Repeater-Builder] Re: Source of Coil Slugs I measured the existing coil slugs as follows; The slugs for L802 through L809 measure 0.129" at the outside of the threads. The slugs for coils L301 and L302 measure 0.180" I didn't measure the slugs for L801, L810 or L811 as those do appear to tune adequately. Hope this helps. Tom DGN --- In [email protected] , "wb6dgn" <tallins...@...> wrote: > > > > Sorry for the lack of detail. The radio is a 42 to 50 Mc. Motran with the "L" > series receiver (same as used in the Motrac). There are a total of 13 tuned > circuits in the front end and multiplier but only 3 of them seem to tune at > all. Those are L801, 810 and 811. The other preselector coils, L802 through > L809 do not tune nor do the multiplier coils, L301 and L302. Interestingly, > the radio does receive a local repeater when I tack a short piece of wire > onto the first mixer input point so, obviously, the multiplier chain is on > the correct harmonic and has some output at the correct frequency. The test > set indication is quite low, however, compared to the original frequency, so > I know that the circuits are not tuned to resonance. I am not able to get > even a strong signal through the front end, though. I did carefully remove > all of the related coil slugs without breaking any of them and will mic them > and repost later this evening. L802 through L809 are ABOUT 3/16" dia and > L301, 302 are about 1/4" but will give more precise measurements later. > Thanks much for the replies and suggestion. There's a good "old-fashioned" > hardware store not too far from me, will check with them tomorrow. > Tom DGN > > --- In [email protected] , "Eric Lemmon" <wb6fly@> wrote: > > > > Tom, > > > > If you identify the make and model of the radio, perhaps someone who has > > gone this route before can comment. Otherwise, carefully remove one of the > > slugs and take it to a good hardware store where you can use a thread gauge > > to identify the thread diameter and pitch. With luck, that store may have > > machine screws in brass and aluminum that can be trimmed to make the proper > > slugs. > > > > 73, Eric Lemmon WB6FLY > > > > > > -----Original Message----- > > From: [email protected] > > [mailto: [email protected] ] On Behalf Of wb6dgn > > Sent: Tuesday, December 15, 2009 8:46 PM > > To: [email protected] > > Subject: [Repeater-Builder] Source of Coil Slugs > > > > > > > > I'm trying to modify a commercial boat anchor from 42 - 50 Mc. up to the 6 > > meter ham band. Not even one coil in the RF preselector and 1st > > oscillator/multiplier chain will tune into the ham band, which is very > > unusual for this radio. There are just too many tuned circuits to consider > > removing coil windings or changing capacitors so I want to try using brass > > or aluminum coil slugs in place of the powdered iron ones now used. Does > > anyone know of a source for these slugs? I can mic. the slug diameter and > > guestimate the thread pitch if anyone has any suggestions. TIA for any/all > > help. > > Tom DGN > > >
