[The last renewal of this page: July 31, 2011]

These are the All tube 50MHz AM/FM Transmitter , VFO, and the receiver (Crystal convertor built in) which I made when I was a senior high student back in 1970.

I was then a senior high student being supposed to study hard for the entrance examination of the university, and had noway to purchase a HF transceiver to realize my dream to enjoy ragchews with U.S. station on HF bands, hanging around on 50MHz doing a ragchew with local stations from morning till late at night being just frastrated. This set of radios used to support very well such my frastrated hamradio life in that era.

After I entered the university, I started to have a part time job to buy Yaesu FT-401D, and at last could realize my dream to enjoy QSOs by phone with U.S. stations, and as I was so happy and excited, that I forgot all the thanks that I had to have and threw away this wonderful homeberw TX and RX. I did not know how much I would feel regret later! With a single bit of 3m/m and a hand drill, I drilled many holes to the thick steel made front panel of the Lead AS-2 cabinet aligning to the line to cut for the meters, cutting with nippers making its blades worn out, making my hand with full of blood blisters and water blisters, causing a loud noise of filing works in all over the house of taking a few nights. I was so stupid to forget those hard work and its super performance to work without any problems for many years, and threw them away in a trash box!

No circuit diagrame is left, and no pictures for inside of the receiver and VFO are left either, and therefore it can7t be an article for homebrewing, however, as these are vintage radios something like fossils in the history, I will just show you their pictures.




From the left to the right, VFO, Receiver, and Transmitter.

A 6CB6 was used for the VFO and oscilates 8MHz, I remenber. The VFO was not very stable so I used to use it mainly for FM to give a FM modulation to the VFO by a varicap, and I used a crystal for the ragchew on AM.

The transmitter has three stages, and a 2E24 (A direct heating tube of 2E26) was used for the final which was relaced to the 6146B later. A modulation was give by 6BQ5 push-pull to the screen grid and the plate. With a crystal microphone of AIWA, the modulation was done with a very real quality and deeply.

The receiver has one RF amplifire and two IF amplifire stages, with a crystal convertor for 50MHz was built-in. It used to work really well and stable.




Believe it or not, there was a time when I set all of these equipments in my bed(!) to enjoy ragchews in bed. I felt in sleep having the standby siemens-key switch down to transmit till the morning many times., hi hi.
So, it is actually a tuff transmitter which cleared severe endurance test many times!




Inside of the transmitter. A good placement in a small cabinet. Well done!




It is also inside of the transmitter. Look at many holes to the aluminum panel aroud the final amplifire instead of a punching metal. A great job doing it with a hand drill.




The reverse side of the chassis of the transmitter. Large resistors are very impressive. Wiring are not beautiful but well done. I can not beleive myself that I made this in my senior high student days.




These are the tool box and parts boxes. Very nostalgic tube parts are impressive, but the tool box is something special. I just can't beleive that I built these equipments with these shabby tools only! Especially, a hand drill with a single bit of 3m/m reminds me of hard work with blood blisters and water blisters, and I'm sure this is only understandable who has the same experience in his history, hi hi.



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