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?

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?

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?

Finalising the Conundrum....

Well,

A few things to report....

Firstly, when I was at the National HamFest the other weekend, I found myself a signal generator. It's a HP8648A and looks like this:

It covers 100KHz up to 1GHz and appears to be calibrated in agreement with my Spectrum Analyser. That's good enough for me and at last I have a Signal Generator where I can specify the output amplitude in dBm!

I've been fiddling today with the transverter project I started back here:

http://g0mgx.blogspot.co.uk/2014/09/to-transvert-or-not-to-transvert.html

and have been making the final component which is a 10W PA to give a reasonable level or RF out. Here's what the PA looks like:

It's based on a 2SC2539 final transistor which is mounted on a reasonable heatsync between the two copper boards you can see. The PA seems to be working with a nice clean output:

The driver transistor (which is a poor old 2N3866) is running hot, hot, hot! I need to find a better component for that bit as otherwise it's going to cook. Something with an isolated can would be ideal so I can solder it to the copper board - that would make an excellent heatsync.

I've stuck the project together now and it's looking like this:

I need to run some more tests on the output to check for harmonics and other spurious emissions, but I think this is good for an on-air test now.

The only other thing to report is that I left my FT-DX3000 WSPRing on 40M last night, I set the RF out to the lowest setting (5W) but also reduced the audio drive so the output was reading 2W on the internal meter. This is the map of heard/hearing this morning:

Florrie cat's not been helping much, sleeping behind the radio PC monitor:

The other three spent most of the afternoon upside down in the kitchen:

Good, egh?

Local conditions.