I was reorganizing my files when I came across this old school tweety bird circuit (circa 1969) for tube-type rigs.
S1 should be SPDT Center OFF (Radio Shack 275-654 or equivalent). Circuit shown has two different sounds selected by S1. VR1 controls the repetition rate. For best results, VR1 must be LINEAR TAPER. All capacitors should be disc-type 200-volt rating or better.
Output of the T.B. circuit should be connected to the input of the audio amp stage that just preceeds the output modulator. For instance, in a Robyn T-240D (Yellow), it would be connected to pin 2 of V5 (12AT7). DO NOT CONNECT DIRECTLY TO THE MIKE AUDIO INPUT.
This old analog T.B. is easy to build and sounds great, especially when compared to the digital BS available today. For you guys who don't like noise toys, I apologize for posting this. 73s.
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S1 should be SPDT Center OFF (Radio Shack 275-654 or equivalent). Circuit shown has two different sounds selected by S1. VR1 controls the repetition rate. For best results, VR1 must be LINEAR TAPER. All capacitors should be disc-type 200-volt rating or better.
Output of the T.B. circuit should be connected to the input of the audio amp stage that just preceeds the output modulator. For instance, in a Robyn T-240D (Yellow), it would be connected to pin 2 of V5 (12AT7). DO NOT CONNECT DIRECTLY TO THE MIKE AUDIO INPUT.
This old analog T.B. is easy to build and sounds great, especially when compared to the digital BS available today. For you guys who don't like noise toys, I apologize for posting this. 73s.
- 399
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