Dylan Windom

Dylan's 5 Tube TRF Radio

Stations Heard: 25

This five-tube TRF receiver started life as a homebrew that was likely built in the mid-1920s. It originally had 1923 and '24 style brass based 201As, but I haven't dated the other parts. It appears that the original builder used a Neutrodyne parts kit (tuning caps, neutralizing caps, and coils) from Bremer Tully. When I received the set, it was in such bad shape that I started dismantling it for parts. Many solder joints could be pulled apart with little effort. Also, everything was covered in decades worth of dust and oxidation.

After it sat for a few years, I recently decided to build my own TRF set using the parts from it. I set to work dismantling and cleaning and polishing all of the components, and I made a new base board with some scrap wood that I had. The bakelite panel shined up nicely with soap and water, and I added some brass flathead screws where the original builder had scribed crude lines above the dials. I also kept the original binding post strips, which sit a bit crooked as they weren't drilled perfectly.

After everything was cleaned up, I secured all my parts to the board according to where they were in the original set. I had torn up the old wiring, so I had to come up with my own schematic to work with. I borrowed ideas from other 1920s sets and received a few tips on taming oscillation from master homebrewer Bill Meacham. This set also gave me my first taste of working with square buss wiring, which I bought from Antique Electronic Supply. Wiring a radio with this stuff is more like solving a puzzle!

I used modern components in three places. A modern .22µF poly-film decoupling capacitor is wrapped in black paper and equipped with solder tabs on each end. Two carbon film resistors are secured inside aluminum standoffs with cardboard washers and solder tabs. They don't replicate original parts, but simply look more appropriate this way.

This radio is no outstanding performer, but so far it will grab the big stations along the West Coast (I am in Oregon) as well as a few smaller ones here and there. I will be building and using two wave traps in order to tame the local stations. Located at 1110 and 1240, these two completely own the upper end of the dial.

I'll quit talking now, and let the pictures say the rest!

Log

Contest Log for LW-MW Class
Received by Dylan Windom using 5-tube TRF

Time: GMT
Location: Redmond, OR

#         Time     Freq.     Station
7/30/07

001       0457      780       KKOH
002       0500      680       KNBR
003       0600      570        KVI
004       0700      540        CBK
005       0715      640        KFI
006       0720     1240       KRDM
007       0725      810        KGO
008       0730      720       KDWN
009       0800      580       KIDO
010       2039     1110       KBND
011       2046      940       KICE
012       2048      690       KRCO

7/31/07

013      0629       610       KEAR
014      0700       850        KOA
015      0715       910       KGME
016      0730      1000       KOMO
017      0758      1050       KTCT

8/2/07

018      0607       750        KXL
019      0642       590       KUGN
020      1029       550       KOAC
021      1114      1160        KSL
022      1119       890       KDXU

8/4/07

023     0613        610       KONA
024     0742        670       KBOI
025     1025        620       KPOJ