MØMCX

Ameritron AL811x 800w tuning tips

Don’t spend your life tuning amps. Do it once with sticky labels and forget!

I’ve recently un-mothballed my Ameritron which has seen good service and delivers 200 watts for 10w drive - ideal for PSK31 and other low-power digital modes. This amp will go further and deliver 400 watts for 30 minutes key-down so it’s ideal for full legal power in the UK.

Anyway, flicking from 80, 40, 30 and 20m during the grey line with the AL811, I’ve discovered that I have never mastered the speedy band switching that some operators appear to have worked out. So I developed my visual system(!) using sticky labels tuned against a 50 ohm dummy load to calculate the fastest (approximate) setting for each band. It works blooming marvelous too!

Since a picture tells a thousand words, I won’t bore you any more. Here’s a close up! http://www.m0mcx.co.uk/pictures/Ameritron_AL-811X.JPG

[Later] - I can’t get 10m to tune. Maybe it’s not an export model? In which case, according to sources on the internet, to convert a non-export model to an export model, one needs to make a mod by cutting a wire. This will enable 12 & 10 meters on the Aux switch. I hate engineering! :)

Cheers, Callum.

May 5th, 2008 Posted by callum | QRO | no comments

Ham Radio Realtime Gray Line

Courtesy of http://www.fourmilab.ch/, this is the current real-time position of the Gray Line, as utilised by Ham Radio operators over the world.

For those who don’t know, the”grey line” is a band around the Earth that separates daylight from darkness as the earth rotates.  Propagation along this line can be very efficient.  One reason for this is that the D layer, which absorbs HF signals, disappears rapidly on the sunset side of the grey line, and it has not yet built upon the sunrise side.

Interesting? Well, I’ve spoken to people on the other side of the planet during this 30 minute phenomenon. It certainly gives you a buzz.

[Later: This damned map can takes ages to load.. Grrr]

Cheers.

May 5th, 2008 Posted by callum | QRO | no comments