[Hallicrafters] S-40

[Burton Pratt K4PRF]

I have just finished restoring what I believe to be a very early S-40 as
it has an electrodynamic speaker as was used in the S-20R.  I think that
most of the S-40s used a regular pm speaker.  The dials are green.  The
chassis is stamped for an 80 rectifier although there is a 5Z3 in
place.  I was unable to find a circuit diagram showing the setup for the
electrodynamic speaker with the field coil being used as a power choke
so I used the S-20R diagram.  Everything seemed to match up OK.  The
serial number of this unit is 51207.

Thanks for the suggestions on getting more zip out of the HT-40 on ten
meters.  Listen for me on 29.05 Mc. or 29.025 in the next week or so.

Having suffered through the restoration of two SX-28As in the last two
years I am beginning work on a straight 28.  It is in retched condition
so will be a challenge.  At least there are no extra holes in the panel
and the receiver has never been modified although there are many things
hanging loose.  The S-meter is damaged so will be trying to locate one.
I have a parts rig but the meter is missing.  When I finish this one I
will have a few parts left for those who are willing to tackle one of
these beauties.

73,

Burt Pratt, K4PRF
pratt at zebra.net