13cm surprise


G0FCU
 

After my test of my 13cm receiver at the local recreation ground with a clear path to GB3FNM failed because I had the LNA connected the wrong way round I had put the kit in the workshop and it has been raining ever since.

This evening I connected a new battery monitor to the battery and thought it would be a laugh to point at GB3FNM. I surprised myself when I heard the weak CW ident. 

Bear in mind that I was inside the workshop (see photo) and the land rises 30m within a couple of hundred metres in the direction of the beacon.

I guess I've got a lot to learn about microwaves and hope to get out and about soon to see what else I can hear.

One question I have is how to switch between the rx and tx paths, what sort of relay should be used (assuming that's the right way to do it)?

73 Simon
G0FCU
IO91se


 

Hi Simon,
In the absence of any other responses, I will answer your question.
Yes, you need a relay to switch the antenna from Rx to Tx. At 2.3GHz it has to be a real coaxial relay designed for the job.
Most people use SMA relays made by Transco, Dow-key, Sage, RLC, Narda etc. All are similar in design and are compact and effective. Though these companies may have merged or changed names over the years, they are still available on the surplus market. Even if many years old they are still  a good bet. I think it is fair to say that very few of us would be looking to buy these new, as the price would probably be horrendous. You could ask here and someone may offer you one at a better price than is sometimes asked on ebay!


G0FCU
 

Thanks for the reply Ken. If anyone has a couple of suitable relays or knows of a source please let me know.

73 Simon
G0FCU.

On Sat, 29 May 2021, 08:34 Ken G3YKI, <kenneth@...> wrote:
Hi Simon,
In the absence of any other responses, I will answer your question.
Yes, you need a relay to switch the antenna from Rx to Tx. At 2.3GHz it has to be a real coaxial relay designed for the job.
Most people use SMA relays made by Transco, Dow-key, Sage, RLC, Narda etc. All are similar in design and are compact and effective. Though these companies may have merged or changed names over the years, they are still available on the surplus market. Even if many years old they are still  a good bet. I think it is fair to say that very few of us would be looking to buy these new, as the price would probably be horrendous. You could ask here and someone may offer you one at a better price than is sometimes asked on ebay!


Andy G4JNT
 

I still have a some spare relays from the spectrum analyser dismantle last year.
Work up to 18GHz, 28V non-latching coil

£18 each if you're interested.

There's a photo of them all somewhere in the archives of this Group dated ~ June/July last year, but I can't find it



Virus-free. www.avg.com


On Sun, 30 May 2021 at 14:47, G0FCU <simon@...> wrote:
Thanks for the reply Ken. If anyone has a couple of suitable relays or knows of a source please let me know.

73 Simon
G0FCU.

On Sat, 29 May 2021, 08:34 Ken G3YKI, <kenneth@...> wrote:
Hi Simon,
In the absence of any other responses, I will answer your question.
Yes, you need a relay to switch the antenna from Rx to Tx. At 2.3GHz it has to be a real coaxial relay designed for the job.
Most people use SMA relays made by Transco, Dow-key, Sage, RLC, Narda etc. All are similar in design and are compact and effective. Though these companies may have merged or changed names over the years, they are still available on the surplus market. Even if many years old they are still  a good bet. I think it is fair to say that very few of us would be looking to buy these new, as the price would probably be horrendous. You could ask here and someone may offer you one at a better price than is sometimes asked on ebay!


Nick Gregory G0HIK
 

Hi Andy,

If the relays are still available, I could make use of them in my BAO 45w amp.

Thank you.

Nick G0HIK


Andy G4JNT
 

Sri
All gone now



On Mon, 31 May 2021 at 16:16, Nick Gregory G0HIK via groups.io <nickg0hik=googlemail.com@groups.io> wrote:
Hi Andy,

If the relays are still available, I could make use of them in my BAO 45w amp.

Thank you.

Nick G0HIK


Nick Gregory G0HIK
 

OK,

Thanks for letting me know.

Nick G0HIK