Re: 6Cm?


Colin Ranson
 

Further to the 5.7GHz posting I bought, from the South Birmingham lads, a pair of transmit/receive boards for 5.7GHz. This was several years ago, I have done nothing with them as yet.  The printed line filters on both boards say 5.4 – 4.9GHz, with extensive use of gasfets. The TX one uses an M76 DBM and the RX a single diode.

 

Anyone any experience of them ?

 

They look very useful,  as soon as I can get a LO running I can at least give the RX one a try, GB3MHZ is only a few Km away.

 

I have some photo’s, if anyone wants a look see I can e-mail them to you, save bandwidth on here.

 

73’s  Colin de G8LBS – suffering ‘man-flu’ from the Covid jab (OAZ) yesterday.

 

Sent from Mail for Windows 10

 

From: John Fell
Sent: 03 February 2021 11:45
To: UKMicrowaves@groups.io
Subject: Re: [UKMicrowaves] 6Cm?

 

Hi Ben,

There was an article in Radcom Microwave column a couple of years back showing how to modify a Franko Sat LNB board to produce a low noise front end for 5.7GHz .

I have one and it has around 1.5dB noise figure and 15dB gain  , which would be a good start towards a TVTR.Followed by an ERA gaas Mod amp .

 

Evanescent filters are easy to make and will give you bandpass after the front end stage .

 

Build/buy a synth board to provide a lockable LO for TX/RX and bosh some i.f. passband filtering together .

  Add a couple of mixer stages and some control system/sequencing and you are there .  

 

The Birmingham lads (G8OHM)  have/had  PA modules at modest second hand prices for 8W output  .

 

I would start with the RX and use the Beacons available locally to you (GB3OHM on .900 and GB3ZME on .910 +/-a few kHz ) .

 

Have added a 5.7GHz VE4MA to my 60cm 10GHz offset dish ,off boresight in the horizontal - seems to have little influence to the 10GHz LNB and just needs you to offset on your rotator readout .

 

Hope to use my Kune TVTR on EME next , after 24GHz tests .

 

Gud Luck.

 

73

John

G0API 

 

It's just stopped raining !

 

 

 

On Wed, 3 Feb 2021 at 10:15, militaryoperator via groups.io <Military1944=aol.com@groups.io> wrote:

Subject: Re: [UKMicrowaves] 6Cm?

If you fancy a build try the w1ghz uses pipe cap filters so fairly easy and not many components.

I can always run tests with you Ben we should have a fairly good path when conditions ok

73 chris G0WUS

 

 

 

Hi Chris. Yes, I have read the W1GHZ bit about his trvrt, and I did buy some copper endcaps to try and make some filters for a laugh, just not got around to it yet. 

 

So far all the bands have been plug and play with a few bits of string between them, nothing that a basic foundation holder couldn't do, hi. SGL for 23, 13, 9 and a Kuhne on 3.  

 

I have bought the BATC 23Cm amp pcb and all the bits, another thing sitting on the self.  I even bought a hot plate to have a go at flow soldering, did try it on a test pcb with a few smd bits, works great so at least I have that tool in the box should I need it.

 

I'll keep thinking on the issue so see you on the other bands till then Chris, hi. 

 

Ben G4BXD 

 

Join UKMicrowaves@groups.io to automatically receive all group messages.