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Saturday, 11 April 2015

Transverting - Finished!

Well,

You may remember the 4M transverter I started making here:

http://g0mgx.blogspot.co.uk/2015/04/transverting-even-more.html

I mentioned that I was waiting for a zlpll from here:

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

to complete the project.

Well, it arrived today and I have installed it in the tranverter:


Marc, ON5VW was kind enough to offer me an on air test, so this is my signal as received in JO10 over the water in Belgium:



So that's the final proof of concept - all working as planed!

Good, egh?

Wednesday, 8 April 2015

Transverting - Complete!

Well,

The 4M Transverter I started back here:

http://g0mgx.blogspot.co.uk/2015/04/transverting-even-more.html

Is now **nearly** complete.I say nearly as I am still waiting for a ZLPLL board from here.

The interior has been completed and all wiring completed, here's a shot mid way though that process:


Now, you may remember that I have a Gemini 4M & 6M amplifier. Well, this was configured for a 25W drive level when I bought it, so I needed to modify it for the lower drive level of this transverter. The amplifier includes an attenuator which needed to be replaced. Here's a view of the Gemini with the covers removed:


In the photo above I have highlighted with a red circle the component that needed to be replaced. You can hopefully see that I have also had to remove the internal covers from the RF board screened enclosure to access the part.

Here's the RF board with the new attenuator installed:


This is working beautifully from the transverter now and giving me full power out from the transverter drive levels.

Good, egh?

Thursday, 2 April 2015

Transverting - Even More More!

So,

Following from the start of the 4M Transverter project I posted about last time:

http://g0mgx.blogspot.co.uk/2015/04/transverting-even-more.html

I've done some more today.

The power amp module is built and mounted on the rear of the enclosure with an aluminium heat spreader:


The rest of the enclosure is prepared:




The internal wiring is almost complete, I've just run out of SMA cables - which is a bit of a bummer! I'm also waiting for the ZLPLL from here to complete the project properly.

Not a bad start though, egh?

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.