Monthly Archives: June 2020

Unadilla 40m trap refurbishment by Nick G0VQO

As I find myself with spare time on my hands during lockdown.

I decided to pass some time resurrecting an 80m/40m  trapped dipole that I had used some years ago but took out of service as the traps had deteriorated.

On inspection I could see that the bolt fixing hardware was corroded and the resin former for the coils was cracked.

After removing them from the aerial  I made notes of how many turns there was on the coil then I removed the wire coil.

This revealed the cracks in the resin formers.  

I decided to use some epoxy resin the fill the crack.

The wire that I had removed was 1.6mm aluminium and it just happened to be the same wire I use on my quad elements.

I wound new coils on the former with an extra turn added.

I then measured the resonant frequency using my analyser and reduced the length of the coil to bring to resonance at 7.1Mhz and repeated the process with the other trap.

Once the aerial was assembled and raised to 40ft at the feed point in an inverted V configuration adjustments were made to the wire length for best SWR.

Its been in the air for a few weeks now and has been performing well.

A big thank you to Nick for the write up and photos

all the best from the Club and Good DX

 

 

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Local Amateurs in Lockdown

 

During Lockdown some local ham have now once again turned to the radio, after repainting the house or doing the gardening.

Many of us Amateur Radio fans have been so lucky not only having family and close friend to talk too in these unsettled times,  but we have access to the world wide airways as well, if your a high risk person living on your own as I know a few, this has been a life line for many and i know a lot can relate to this.

we have seen Covid 19 nets pop up on HF, VHF, UHF, DMR, and all modes, all sharing a common goal and getting people to talk and meet new hams alone the way,  I know in my town Kingston Upon Hull there are quite a few local ham building antennas and  repairing and trying new thing out and having fun.

  I have been talking to a few and watching over the last few months what they have been doing, I have ask a few to take photos and do a little write up of what they have been up to.

First to reply Was Nick G0VQO on his 40m / 80m traps he repaired enjoy the write up Nick kindly sent in, we will have more to follow i am sure.

  

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