ubitx 5 continues to perform well. Got digital modes working great and also making contacts on SSB phone.
My question - does anyone have any experience using ubitx to drive an old-school vacuum tube linear amp. I have a Collins 30L-1 (4 811 tubes) that I use with my Kenwood. Is it possible or even a good idea to try to make it work with the ubitx. I need to figure out what it would take to bring out the PTT to drive the TX/RX control on the amp. With the Kenwood I bought a commercial interface that plugs directly into the accessor port of the Kenwood.
Any thoughts or ideas would be greatly appreciated!
Last year I fed my BitX40 into a homebrew grounded grid sweep tube amp.(which I think is more boat-anchorish than Collins, no offence.) This amp has spent nearly 20 years sitting in a shed in Hawaii, thus the rust and conversion of anything nickel into a living organism. But I drug it out and turned on the generator, and placed my life in Pelee's hands. As I remember, with 6 watts out of the BitX40, I was approaching 100w Input on the amp . I tested it out with another ham maybe 80 miles away. He heard no distortion of loss of quality when the amp was on.
That's great, that it worked so well. I know I need to put a beefier relay in to switch the amp to TX. I know I need to put a diode across the relay coil to protect the uBITx I'm looking fir advice / schematic on wiring the relay and where to connect to the uBITx to pick up PTT to switch on the relay.
The external commercial relay I have on the Kenwood by radiodan will work if I replace the kenwood cable, but I'd prefer to build it in to the case.
The PTT picture you sent was just a thumbnail and I couldn't make out any details.
Dean, your 30L-1 likes to see 50 watts or more to start to make good power. While it should amplify the output from a ubitx, it's a kilowatt-class amp with only 10 or 12 dB gain.
So with the nominal 10 watts out of a a ubitx, you'd see about 100 watts out of the 30L-1, which is hardly worth lighting the filaments for -- at 25 watts per filament, you do the math.
You'll need an amp better suited to the semi-QRP output of the ubitx, and capable of handling the higher output on lower frequencies and lower output on higher frequencies.
I'm not saying you can't use your 30L-1 with a ubitx. However, you may want to track down a "two-pill" CB amp to put between the ubitx and the 30L-1.
