MA350B Decade Frequency Generator



This unit is what would today probably be called a Synthesizer unit.It is for use with the RA117 and the MA79 drive unit .This set is fully transistorized and has been made in "modular" form which simplifies things when the unit goes faulty and you can replace the module in question.If,however you have no spares and have to work on the unit things can become a bit tricky.The connectors to each module have a number of cables to each one and will not enjoy being twisted back and forth too much..! repairing a broken wire then becomes a bit of a problem..!

The MA350 is quite complicated and I have found that a fair bit of patience was needed to repair and align it.

You work it in this way.You set the required MHZ range on the RA117 or MA79 in the usual way.The 350 is then used to set the KHZ reading on the main set,the five rotary switches setting the 100khz,10khz,1,khz,100hz ranges with the last a fine tune.This produces an accuracy of 1hz.(although I have found that despite careful adjustment mine cannot achieve this).

The MA350 has two identical outputs of the following:-

3.6-4.6 mhz.





The reason for two outputs is so that the MA350 can feed either a RA117/MA79 combination or two RA117 for diversity reception.

An external reference source can be fed to the unit (such as MA259) to improve stability over the internal frequency standard.

The meter on the front panel gives reading on the locking condition of each decade and also of the level of the 3.6-4.6 mhz output.

Overall a very nice piece of kit to have.

Various models.

MA350A Standard Version
MA350B For use with RA117/RA127/MA970
MA350C Modified for electrical decade selection
MA350D Modified MA350B with MA357 1.7 Mhz mixer unit to give remote tune of +- 1 Khz
MA350E As MA350B less internal Frequency Standard.

Updated 03/05/2002

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