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Monday, 23 December 2013

Extreme, wow that's Extremely Extreme!


Thinking about Lindy that I made back here:

I ordered a 144-145 MHz pre-amp kit from Amsat-UK:

The design was published in September 2012 OSCAR News.

I've done quite a bit of SMD kit building in the past, AKA Extreme Soldering - but this was a whole new challenge! The components in this were the smallest I've ever come across - this was really tricky!

The image above should open in quite high-res so you can see the effort I have made of the soldering. It's quite poor really, but it certainly works as you can see below. The odd looking peaks on the far left of the spectrum are harmonics from my 10MHz frequency reference (I think):

It's already mounted in a die-cast box and the power is fed down the coax. This should work directly with my FT-847 which can provide coax based power to external pre-amplifiers.

I'll have to see how the satellite passes look tomorrow with this amplifier in-line - ideally I should mount this at mast head end of the coax to amplify any signals that are lost in the coax run. I've got about 20 meters of Westflex 103 and the losses at 145MHz are quoted at 4.5dB per 100M. I make that a possible loss of 0.9dB. Let's try using it at the shack end and see what happens.

Interesting, egh?

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