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
> >
>


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