This is the second Ca. 1934 TNT CW Transmitter in the NEWSM collection. Please see the George Grammer Designed TNT (Tuned-Not-Tuned) Transmitter #1 for design details and reference material.
This TNT Transmitter was build by the late Merrill Peckham Budlong W1MB, an avid amateur radio operator, past director of the NEWSM, and owner of Budlong Marine Radio. As with TNT #1, it is built according to the plans in the December 1929 issue of QST magazine with updates published in the 1934 ARRL Handbook. This one has a Sylvania VT-25-A tube (7.5V Filament, 425Vmax @ 18 mA) that is the same as the RCA UX-210 tube used in TNT #1. As with TNT #1 the plate and grid coils are configured for operation at 3.5 MHz (80 Meters).
The transmitter came with a filament (7.5V) and plate (400V) power supply. On 9/21/23 we slowly brought the power supply back to life, connected it to the transmitter, and successfully sent CW signals to a National HRO 60 receiver. We will use this transmitter during the Antique Wireless Association Bruce Kelley Memorial QSO Party in November.
Click on an image below to see a slideshow or a larger view.
References for TNT (Tuned plate Not Tuned grid) transmitter
- Building A 1929 Style TNT Transmitter, well illustrated build by VE7SL, Steve McDonald
- Planning and Building Transmitters, form 1934 ARRL Handbook (also referenced in above text)
- The Planning and Building of an Award-Winning TNT, by Nigel Wiegand, W0VLZ. Includes links to
videos of the TNT transmitter that he built. - The Saga of the TNT Transmitter, 1981 story of how W2SN addressed numerous hurdles while
building his TNT transmitter - The Single Control Transmitter, by George Grammer, Dec., 1929 QST (also referenced in above text)
- The TNT – A 1929 Single Control Transmitter, by Steve McDonald, reference on the Antique Wireless
Association Project Files page. - Vintage CW Transmitters, by Gary Poland. Illustrates and describes several reproductions of classic
1920s transmitters, including the TNT built by Gary Poland, W8PU