SB220 SB200 SB-221 SB201 Relay 120Vdc
SB-200 SB221 SB201 SB-220 Antenna Relay
Installation Instructions Heathkit 69-55 or Heathkit 69-5 improved relay system
The patent pending RL3pDT120dc is a superior replacement for the Heathkit K1 69-55 relay, Heathkit 69-5 relay, and similar 110 or 120Vdc linear amplifier relays including Collins and other brands.
There is no longer any need to use hard-to-find slow obsolete relays in SB200, SB220, SB230, Collins, and other amplifiers using high voltage dc antenna transfer relays.
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Universal 120Vdc relay contact timing tests
This board is a direct drop-in superior replacement for all 120Vdc antenna relays used in SB220, SB200, Collins 30L-1, and other 120Vdc antenna relays.
This board is time-sequenced to always close antenna contacts slightly before and hold the antenna contact closed slightly after the control signal and input/bias relay release.
Yellow color = relay keying line (20V per division)
Aqua color = RF Output Close time: 4mS
Red color = RF Input and bias contacts: 7mS
Green color = unwanted back-pulse
Isolated bias contact closes with input RF relay.
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Wiring connections Heathkit 69-5 69-55 120Vdc relay (patent pending)
This board is 1.5″ wide x 1.75″ deep x less than 1″ tall.
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SB200 Antenna Relay
Sequenced 120Vdc relay system board only $59.00 shipped USA
Sequenced 120Vdc relay system board with all necessary hardware and cables $69.00 shipped USA
Parts ORDERS or parts questions go to orders@ctrengineeringinc.com