07-08-2024, 05:26 PM
Hi Doug,
The wire is about 1.5 metres above the edge of the roof. Not ideal, I agree. I have a cunning plan to raise the centre pole another metre or so but that will be about the limit due to mounts being screwed to the C sections of the shed. I need a chance to get to HammerBarn to get some (more) bibs and bobs.
The G5RV *should* present 50ohms at the feed point at the anointed frequencies, so I have 1:1 choke fitted.
The VNA grab is misleading, due to a PEBKAC error (Problem Exists Between Keyboard And Chair). Apparently the model I have has 101 data points and I swept from 6.9 MHz to 30 MHz. With the narrowness of the bandwidths I suspect it simply bypassed some of the dips.
I will retest using smaller slices around the predicted frequencies.
The other idea is that there is a 4m gap between the two sheds. I will rearrange the antenna so that the "active" leg passes over the gap, with the "counterpoise" leg over the long shed. Will it make any difference? Who knows? It won't take a lot to try...
Time is the killer at the moment. Hopefully at the end of the year I will be able to give full-time work away. (If anyone around VK5 needs a part time Technical Author and Illustrator from next year, don't be afraid to sing out...)
The wire is about 1.5 metres above the edge of the roof. Not ideal, I agree. I have a cunning plan to raise the centre pole another metre or so but that will be about the limit due to mounts being screwed to the C sections of the shed. I need a chance to get to HammerBarn to get some (more) bibs and bobs.
The G5RV *should* present 50ohms at the feed point at the anointed frequencies, so I have 1:1 choke fitted.
The VNA grab is misleading, due to a PEBKAC error (Problem Exists Between Keyboard And Chair). Apparently the model I have has 101 data points and I swept from 6.9 MHz to 30 MHz. With the narrowness of the bandwidths I suspect it simply bypassed some of the dips.
I will retest using smaller slices around the predicted frequencies.
The other idea is that there is a 4m gap between the two sheds. I will rearrange the antenna so that the "active" leg passes over the gap, with the "counterpoise" leg over the long shed. Will it make any difference? Who knows? It won't take a lot to try...
Time is the killer at the moment. Hopefully at the end of the year I will be able to give full-time work away. (If anyone around VK5 needs a part time Technical Author and Illustrator from next year, don't be afraid to sing out...)
Colin
Barossa Valley, SAP. PF95ln
(aka VK5CSW)
Barossa Valley, SAP. PF95ln
(aka VK5CSW)