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AM transmitter issues
#3

+1 on what Vinzer said. However, check the carrtridge. Most "phono" preamps, especially those little boxes with no controls) are for magnetic cartridges. If the RC/88 has a crystal or ceramic cartridge in it, it will overdrive a magnetic preamp. Plug the preamp that the RC88 is feeding into the "line level" input of an amp, to confirm that it works. If the Spitfire has a "line level" input and the phono and preamp are functional, distortion should not be an issue. Otherwise, get a 100K audio taper pot, connect the output of the preamp between the 2 outer legs (ensure the leg closest to minimum is the common), and the transmitter between the center (wiper) contact and the common leg.

Hopefully this works.

Re the SSTRAN, I understand that they stopped making them but still support them. If possible, tune the SSTRAN to an OCCUPIED channel, turn it off and tune that channel on the radio. Power up the SSTRAN. If no difference is heard, the transmitter is dead. I don't know how many stages that there are to the transmitter, but either the oscillator, RF amp or power is the issue. If the unit was run without an antenna or a poorly matched antenna, the output transistor may have blown (although these are only 100mW units and I hope that the output transistor was a little heftier than that). Do you have a schematic? Post it, and we all will see if we can help. I don't have the SSTRAN (I have a Vector kit and a Talking House) but several other Phriends on the Phorum do have them.

"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis

Best Regards, 

MrFixr55


Messages In This Thread
AM transmitter issues - by oldschoolphotoguy - 04-15-2023, 06:39 PM
RE: AM transmitter issues - by vinzer - 04-15-2023, 08:03 PM
RE: AM transmitter issues - by MrFixr55 - 04-16-2023, 10:37 AM
RE: AM transmitter issues - by Radioroslyn - 04-16-2023, 12:02 PM
RE: AM transmitter issues - by radiorich - 04-16-2023, 02:33 PM
RE: AM transmitter issues - by oldschoolphotoguy - 04-21-2023, 05:51 PM



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