I want to connect a Yaesu FL-2100b HF Linear amplifier for use with the Kenwood TS-440 HF transceiver. I have read in this forum that the TS-440 does put out enough voltage to activate this amplifier, any other solutions? - tks
Your understanding of how an HF amplifier is "keyed" is INCORRECT.
I don't understand why so many new radio amateurs get this wrong.1. The Yaesu FL-2100b has a 4 screw terminal strip on its rear panel.
2. One pair (2 screws) on that terminal strip are marked RLY (Relay).
3. These screws have VOLTAGE (They are HOT).
4. IF those 2 screws are SHORTED (switch), the FL-2100b is turned ON !
==SO==
5. The TS-440S, or any HF transceiver DRIVING this amplifier ONLY ACTS AS A SWITCH.
6. WHEN you push the PTT on your TS-440S, a set of contacts (REMOTE, 7-pin DIN) are CLOSED, to SYNCHRONIZE the TURN ON of the FL-2100b amplifier.
7. The TS-440 is the orchestra conductor, when PTT is depressed, the T/R relay switches from receiver to transmitter, contacts are closed that turn on the amplifier, RF is generated, and the FL-2100b amplifies that RF power.
8. When the PTT is released, those steps are reversed -- and then your receiver functions.