Thursday, 2 April 2015

Transverting - Even More!

Well,

Following the success of my 2M transverter project back here:

http://g0mgx.blogspot.co.uk/2014/10/transverting-some-more-some-more.html

which I showed off working here:

http://g0mgx.blogspot.co.uk/2015/03/ts-990-on-2m-144mhz-no-way.html

I decided that I would like to have a bash at making one of these transverters for 4M. Sam, G4DDK agreed to supply me with a kit of parts for a 4M variant of the Anglian. There are about 40 or so component changes. This meant that the board needed the SMD soldering to complete the unit - the 2M version required no SMD soldering!

So here is the project in it's infancy:


And here with quite a few more components in place:


and here with it complete and in the tin screening box:


I've run all the basic tests and both the RX converter and TX converter are working fine. There is a 42MHz local oscillator (70 - 42 = 28) - as with the 2M variant, I have ordered a ZLPLL board from here:

http://zl2bkc.com/projects/zlpll/

to provide an external frequency reference to stabilise the on board LO.

I've started the PA board to go with the unit; it should deliver about 7W output.


I've decided that to avoid any switching between transverters I will leave the 2M box interfaced to the TS-990 and use this 4M variant with the FT-DX5000. That has a transverter output which is -10dBm rather than the 0dBm I require. I may have to experiment a little with the levels but I should be able to drive the 4M Gemini amplifier perfectly with this combination.

Let's see.

Freddy cat has been doing a fine job of being almost completely in the way throughout.


Local conditions.

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