Remler IF Transformers
Outside views of the Remler 600 and 610 transformers (top) and inside view of the Remler 600 transformer (bottom). The Remler 600 is an iron-core non-tuned transformer and the Remler 610 is an air-core filter transformer (tuned with a .00025 mfd capacitor across the secondary winding). With reference to the Remler 600 transformer at bottom right, the single primary coil (tan) is sandwiched between the two secondary coils (green). The secondary coils are in series. Photo courtesy of Chuck Doose.
At the present time I do not own a Remler superheterodyne. However, I have had access to two different sets in the recent past where I was able to measure the bandpass response of the IF transformers. The Remler transformers are manufactured better than most of the other 1920s IF transformers and I have never had a problem with them. The two tables below record the bandpass measurements that I made. The type 600 transformers were measured with the secondary of the transformer referenced to A-. The type 610 transformers were measured with the secondary of the transformer referenced to A+ and the grid leak resistor and capacitor in the circuit. For a complete engineering analysis of the Remler 600 and 610 transformers see the research paper by Chuck Doose here.
Advertisement for Remler superheterodyne parts from the Fall, 1924, Citizens Radio Call Book.
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Type |
Peak Freq. |
Lower 3 dB |
Upper 3 dB |
Bandwidth |
Relative gain |
Pri. ohms |
Sec. ohms |
#1, 600 |
46.5 KC |
25.8 KC |
91.1 KC |
65.3 KC |
12.4 |
70.1 |
290.1 |
#2, 600 |
45.5 KC |
24.8 KC |
97.0 KC |
72.2 KC |
12.4 |
81.2 |
274.1 |
#3, 600 |
46.5 |
25.3 KC |
96.0 KC |
70.7 KC |
12.6 |
81.9 |
282.5 |
#4, 610 with .00025 cap |
48.1 KC |
46.3 KC |
49.8 KC |
3.5 KC |
6.7 |
33.4 |
162.5 |
Type |
Peak Freq. |
Lower 3 dB |
Upper 3 dB |
Bandwidth |
Relative gain |
Pri. ohms |
Sec. ohms |
#1, 600 |
46.3 KC |
25.7 KC |
89.7 KC |
64.0 KC |
13.4 |
73.7 |
270.7 |
#2, 600 |
46.3 KC |
25.9 KC |
90.3 KC |
64.4 KC |
13.2 |
75.9 |
266.4 |
#3, 600 |
47.3 KC |
26.2 KC |
93.9 KC |
67.7 KC |
12.8 |
81.7 |
283.1 |
#4, 610 with .00025 cap |
46.6 KC |
45.16 KC |
48.16 KC |
3.0 KC |
8.0 |
33.4 |
151.4 |