Search This Blog

Radio Guy Tees

Radio Guy Tees
Radio Guy T-Shirts

Monday, 30 May 2016

4M - Alive and well?


Some interesting propagation on 4M today. A beacon very loud from JN86:

Here's the 4M map from the great

Definately experiencing some "local conditions"

Good, egh?

Friday, 20 May 2016

Frequency Reference Completion


The project from last time is even in a box now:

Good egh?

You will see that we adhere to strict rules whereby the dogs are not allowed on the furnature:

Local conditions.

Tuesday, 17 May 2016

More Frequency Reference


Following my musings last time over the QRP Labs GPS module, I've now also built two further kits from QRP Labs. The S5351A Module and the VFO.

When you combine all these together in the way I have you can create a GPS disciplined frequency reference with two outputs.

One of the outputs can be fixed in the firmware and I plan to put mine on 10MHz, I've made a low pass filter for this output to clean out the harmonics. The other output can be user set to any frequency up to about 290MHz or so.

Here's the LPF for the 10MHz output:

And here's the 10MHz output before the LPF:

and after:

All good, egh?

Sunday, 15 May 2016

Frequency Reference


Been thinking for a while that my shack frequency reference is a bit old hat and could be a bit more useful. What I would really like is a GPS disciplined VFO so I can set the frequency for my needs rather than only having 10MHz, 5MHz and 1MHz outputs as I do from the old project here:

So I have started to look at the possibility of using a newer device like the Si351A from Silicon Labs.

The first part of the project will be a new GPS receiver to give us the 1pps signal we need for the frequency control. I found a really neat kit at QRP Labs

I've built the kit today and it looks like this:

Mine has been built to utilise an external active GPS antenna.

The output from the 1pps looks like this on the 'scope:

So all seems well with the first phase.

More to follow!

Here's our Pepper Cat who has been almost completely in the way most of today:

Local conditions. Good egh?

Friday, 6 May 2016

IC-7300 - the first Casualty?


You will remember last time that I came home with a new IC-7300. I've played with it quite a bit and it seemed to be an excellent radio with very good close in signal rejection on receive.

Yesterday I was using the radio on WSJT and noticed that even though the power output was set at 40% and the audio drive levels set such that the output power was 25W, when the radio entered TX the PO meter shot up to 100%, then almost immediately back to 0% and then crept up over 3-4 seconds to the 25% it should be at. This was looking like the worst ALC overshoot I had ever seen - I wondered if this was something to do with the new firmware upgrade.

Anyhow, a few minutes later the radio started to "re-boot" on entering TX. I checked all the obvious things like PSU voltage and SWR et cetera, then I simplified the setup.

I have a very simple PC based audio tone generator so I set that up to generate a 1200Hz tone on the USB audio device from the IC-7300, then when I put the radio into PTT using either a CAT command or the mic PTT the radio "re-boots".

Here's a video showing this:

So, the radio has gone back to Icom....

Here's Bonnie Dog and Miss Luna Cat who appear to be the very best of friends:

Local conditions.