My Freed-Eisemann FE-15

© Copyright Alexander D. Schapira, 2005, All rights reserved

With thanks to all who helped and provided information and
encouragement, I am happy to say that I have gotten my
Freed-Eisemann FE-15 working. For those interested,
here is what I have done so far, and what remains to do:

While on vacation last summer I visited an antique store in Eastern Massachusetts
where I found the chassis of a Freed-Eisemann FE-15.
It was wrapped in old newspapers from 1964, but never-the-less was covered in grunge.
All five UV-201A's were there, but it had no cabinet and was missing two of the three large knobs
and both of the smaller rheostat knobs.  I decided to take a chance on it.

After the initial cleanup, it looked like this.
BEFORE/FE15top.jpg 

I downloaded a schematic from Nostalgia Air (Thanks!).
 Two of the UV-201A's had open or intermittent filaments, or so it seemed.
 Two of the transformers had open windings,
 and the two wire-wound resistors, and the grid leak resistor were open.

I have never worked on a TRF set before but I was
 encouraged by list members to attempt a repair.
Here is what I did.
I unsoldered the pins and gently removed the old cement,
separated the base from the glass, cleaned and tinned the leads,
re-glued the base (using Elmer's White, per previous discussion)
and re-soldered the pins.  Both now have solid connections and
work fine in the FE-15 and in a test jig.



BEFORE/FE15res.jpg  GridLeak2.jpg

WireWound1.jpg

One of them (on the left, below) was itself a replacement transformer that had gone bad.
I now know that open transformers are very common in sets of this type
because of the fine wire used in the transformer windings.

BEFORE/FE15Xfrmr1.jpg  BEFORE/FE15Xfrmr2.jpg

I used RC coupling to get around the open transformers.
For the coupling from the detector to the 1st audio stage,
 I used 100k in the detector plate through .1 uF to 1 Meg at the 1st AF grid to C-.
 (Only the secondary of the 1st transformer was open,
but I removed the primary lead when I inserted the 100k detector plate load.)

For the 2nd audio stage and I used 100k in the plate of the 1st AF stage,
coupled with .01 uF to 1 Meg to C- in the grid of the 2nd AF stage.
(Only the primary of the 2nd transformer was open,
 but I removed the secondary connection too).

 These values were determined empirically using
RC substitution boxes adjusted for best results.

Here is what the lash-up looked like on the bench.

OnTheBench2.jpg

Not having any suitable high impedance speaker to plug into the
output jack, I used a 10k resistor (the output jack is in the
plate circuit to 90 volts) and coupled a little transistor
amplifier to it. (The value of 10k was again determined
experimentally.) Voila! AM stations heard!
I was lucky enough to get an original FE-15 cabinet
and two original large F-E type 360 knobs thanks to Travis Ogden, a reader of my initial post.
The cabinet needed major work.
(Notice someone had attached the top to the lid.)

Before
BEFORE/pict0007.jpg BEFORE/pict0008.jpg BEFORE/pict0027.jpg

After
AFTER/pict0009.jpg AFTER/pict0010.jpg AFTER/pict0025.jpg

 I used gold acrylic paint and wiped off the excess around the engravings.

BEFORE/pict0002.jpg AFTER/pict0012.jpg

(This is reversible if I locate the appropriate transformers.)
AFTER/pict0003.jpg
I measured the current draw on the bench and found that I needed
      A supply:        6V @ 1.0 - 1.25 A
B1 supply:  90V @ 11 - 15 mA
B2 supply:  22 1/2 V @ 0.55 mA
C supply:  -4 1/2 V @ 0.7 uA
I used transformers and parts on hand to incorporate
a regulated 6 volt DC supply for the filaments,
zener regulated B+ supplies, and
a regulated -5 volt C- supply.
I found that I got sufficient audio output using a 5" speaker
with an output transformer from my junk box.
 I mounted the speaker in an old wooden speaker box that I refinished.
But I would like to find a more appropriate speaker.
Any recommendations for an appropriate speaker or horn?
I obtained a copy of the original battery interconnection diagram,
 thanks to Tom Provost, a reader of my initial post.
This is attached to the back of the set and serves to
 identify the function of the seven binding posts.
AFTER/pict0001.jpg

Here is the finished product!
AFTER/pict0017.jpg
Only the two small rheostat knobs are not original.
Does anyone have two original F-E type 385 knobs?
These are engraved 0 - 100 around 270 degrees, and are about 2 1/2" in diameter.

I really enjoyed this restoration project and learning about and listening to a TRF receiver.
  Now I truly know where the expression
"Stay tuned"
comes from.

Thanks again for your help, advice, opinions, comments.

-Al

Please feel free to contact me at the address below:
w2ads@arrl.net.net

Page last modified 12/29/2005