Fianlly!

[K9STH]

I finally got off of my posterior and finished my 222 MHz transmitting converter. All I have to do now is to finish the linear amplifier and to couple the transmitting converter to one of my receiving converters to complete the transverter. I should have the transmitting converter and the receiving converter hooked up later today. I have been trying to decide if I want to use my Centimeg converter (nuvistor model) or one of my Ameco nuvistor converters. Both work very well on 222 MHz. Also, I do have a receiving preamplifier with less than 0.5 dB noise figure that I can add if necessary.

The transmitting converter uses "hollow state" (vacuum tubes) and is running a little over 3 watts output. Starting out with a 43.000 MHz crystal (triode section of a 6U8) then into a X4 multiplier (the tetrode section of the 6U8) to 172 MHz. Next comes a 6AK5 amplifier (172 MHz) which drives a 6360 mixer. I am using a 6-meter (50 MHz) transceiver (Yaesu FT-690 RII with the "snap on" linear amplifier removed) at 2 watts for the i.f. That 6360 drives a 2nd 6360.

The 6360 tubes run a little warm so I may have to "play around" with the bias to see if I can reduce that a little. But, after procrastinating "for ever", I finally finished the transmitting converter.

Glen, K9STH

[N0WVA]

Sounds like your having some fun with this project. Ive never messed with homebrewing VHF stuff. I bet it works FB.

[AB8RO]

I finally got off of my posterior and finished my 222 MHz transmitting converter. All I have to do now is to finish the linear amplifier and to couple the transmitting converter to one of my receiving converters to complete the transverter. I should have the transmitting converter and the receiving converter hooked up later today. I have been trying to decide if I want to use my Centimeg converter (nuvistor model) or one of my Ameco nuvistor converters. Both work very well on 222 MHz. Also, I do have a receiving preamplifier with less than 0.5 dB noise figure that I can add if necessary.

The transmitting converter uses "hollow state" (vacuum tubes) and is running a little over 3 watts output. Starting out with a 43.000 MHz crystal (triode section of a 6U8) then into a X4 multiplier (the tetrode section of the 6U8) to 172 MHz. Next comes a 6AK5 amplifier (172 MHz) which drives a 6360 mixer. I am using a 6-meter (50 MHz) transceiver (Yaesu FT-690 RII with the "snap on" linear amplifier removed) at 2 watts for the i.f. That 6360 drives a 2nd 6360.

The 6360 tubes run a little warm so I may have to "play around" with the bias to see if I can reduce that a little. But, after procrastinating "for ever", I finally finished the transmitting converter.

Glen, K9STH

pictures or it didn't happen....:)

[K9STH]

Here are photos of the 222 MHz transmitting converter. I coaxed it up to 3.5 watts output.

Glen, K9STH

[K5UOS]

Glen,

Your homebrew looks first class. The 6360 Twin Tetrode is a new one for me. At first I thought it was a typo error and you meant 7360.

I have never built hollow state above 10M but I know it is a different ball game.

Thanks, very inspiring .. K5UOS

[K9STH]

The 6360 has a brother, the 6939. The 6939 will go quite a bit higher in frequency than the 6360 but with a little less power. There are quite a few twin tetrode tubes that were designed primarily for VHF/UHF including the 832A, the 6907, the 829B, the 5894, and 8643 among others. Those tubes are much larger and use a special tube socket. The 6360 and 6939 use a "standard" 9 pin miniature socket.

Motorola, General Electric, and several of the commercial two-way manufacturers used either the 6360 or 6939 in a number of their UHF tube type equipment in the lower stages. Also, the old Drake Marker Luxury 2-meter FM transceiver used a 6360 in the final. In addition, the Gonset Communicator IV used 6360s in the transmitters for 50 MHz, 144 MHz, and 220 MHz.

The 6360 is known in Europe as the QQV03-10. The other dual tetrode tubes also have European numbers and were made by Mullard, Amprex, and other manufacturers.

Glen, K9STH