[Boatanchors] Lettine 240 Transmitter Plug In Coils

[LEE BAHR]

As I mentioned earlier, the Lettine is a rats nest under the chassis. 
Everything needs to be replaced including the AC line cord.  The transmitter 
was modified to include a changeover relay which is also in a rats nest 
fashion plus much of the cloth wiring looks like it could stand replacing. 
Combine this with the fact many of the tie points have no lugs but are just 
"free in the clear floating connections", I decided I will "strip the 
chassis down and start over.

I ordered all new caps and resistors plus a 3 prong power cord yesterday 
from Mouser for the re-construction.  Lettine placed some of the parts in 
some really strange places.  Because of this,  I am not sure I want to 
remove everything at once and then start over or just replace everything 
section by section.  I am inclined to do it the later way as the wierd parts 
placement at times plus the lack of tie lugs, which I plan to add, lead me 
to believe I can keep parts placement closer to original specs if I do it 
section by section.  I'll probably start with the power supply and then move 
on to the oscillator and then to the final.  Once the RF is working,  I'll 
move on the to audio input and modulator stages.  The only problem doing the 
restoration this way is it is going to be harder replacing point to point 
wiring.  (I think I need to take a few pictures of it as it now stands in 
case I run into trouble.  I am a little nervous of using the BAMA manual as 
it was "re-drawn".  (I already found three small mistakes in the BAMA 
re-drawn schematic).

When ordering the new parts,  I ordered much larger wattage resistors then 
the originals to make the new parts closer in size to the originals as many 
new parts of the same wattage are much smaller today.  Instead of 8 mfd 
filtering I will have 16 mfd of power supply filtering.

The plate choke and parasitic supressor as original are a real joke.  I am 
seriously thinking of putting in a real multi-pi RF choke feeding the 807 
plate and also put in a more standard parasitic supressor on the plate lead.

As it stands, this is a real complicated restoration when you consider this 
is a simple transmitter with not too many parts.  The unorthodox layout, bad 
wiring job, lack of tie points and rotted wires all make the restoration 
difficult more difficult.  Once restored, the bottom chassis will look very 
unencumbered and look like it was a piece of cake to restore.

Then, comes the restoration of a plug in coil set for this transmitter. 
This is a "cool" kind of rare transmitter.  If it were not for it's great 
outside appearance, the time spent restoring this transmitter could not be 
justified.  When finished it will be a jewel, but you could never get your 
time and money out of it if you ever would want to part with it.  I know 
this going into the restoration.  As I mentioned earlier,  a WRL Globe Scout 
40A looks like a Collins internally compared to this rigs guts.  The Lettine 
cabinet, front panel and transformers were all first class.  From that point 
on it was all downhill.

Lee, w0vt