Transverter range

VK4BXI
Posts: 62
Joined: Sat May 22, 2021 11:44 am
Location: Brisbane

Transverter range

Postby VK4BXI » Thu Nov 18, 2021 6:37 am

Hi all,
in Australia I find the top end of 70cm is at 440 MHz (local repeater at 439.975) I am wondering the best way to get coverage given the nominal IF range of 28 - 32 MHz . Will the 7000 mk2 stretch above 32MHz ? a LO of 404MHz will give me 432MHz to 436 MHZ nominal. Would the best be to try for a unit that has two LO frequencys of (say) 404 and 408 MHz ?
I gave up my Flex 5000A with its 2/70 capabilities and would like to get to something similar with my 7000. But at the moment there doesn't seem to be a simple way of getting there.

Bob
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: Transverter range

Postby w-u-2-o » Fri Nov 19, 2021 3:25 pm

I was hoping someone with transverter experience would chime in, because that would definitely not be me!

However, since nobody is posting, I'll make a suggestion: assuming the transverter allows it, there is no reason to restrict your operations to the range of 28-32MHz. Any Apache labs hardware will operate continuously from well south of 1MHz to just about 60MHz. To enable operations outside of standard band limits the "extended" region option in Setup > General > H/W Select can be used in Thetis. This option exists for many valid and legal reasons, such as this case, MARS operations, to use the radio as a test instrument, etc.
VK4BXI
Posts: 62
Joined: Sat May 22, 2021 11:44 am
Location: Brisbane

Re: Transverter range

Postby VK4BXI » Wed Nov 24, 2021 6:43 am

Ok I've answered my own question.

I set up transverters in the setup table for 2M and 70CM. I then did some injection of 28 to 40 MHz into the transverter input and checked what happened when on the transverter bands.

Basically as you go through the band the providing you have setup the top limit frequency on the transverter correctly and the "Lo" oscillator is defined correctly you can keep going all the way up. So I set the Lo on the 70CM to be 404MHz. And the minimum frequency to be 432MHz and the maximum frequency to be 440 MHz. As I tuned the signal generator from 28 MHz up to 36MHz the signal appeared to move from 432MHz through to 440MHz. Thats all fine and perfect. I did note that the various HF low pass and band pass filters correctly switched in and out as I went through from 28 to 36 MHz so that all seems to work. I did have a few hassles getting things to work and saving the TX profile and switching on and off a couple of times fixed that.

So as noted by WU2O the transverter range appears to be anthing you want it to be as long as its somewhere in the HF bands I.E. 1 - 60 MHz.

Bob
N9SSW
Posts: 14
Joined: Sun Feb 24, 2019 10:25 am

Re: Transverter range

Postby N9SSW » Sat Feb 05, 2022 6:37 pm

VK4BXI wrote:Ok I've answered my own question.

I set up transverters in the setup table for 2M and 70CM. I then did some injection of 28 to 40 MHz into the transverter input and checked what happened when on the transverter bands.

Basically as you go through the band the providing you have setup the top limit frequency on the transverter correctly and the "Lo" oscillator is defined correctly you can keep going all the way up. So I set the Lo on the 70CM to be 404MHz. And the minimum frequency to be 432MHz and the maximum frequency to be 440 MHz. As I tuned the signal generator from 28 MHz up to 36MHz the signal appeared to move from 432MHz through to 440MHz. Thats all fine and perfect. I did note that the various HF low pass and band pass filters correctly switched in and out as I went through from 28 to 36 MHz so that all seems to work. I did have a few hassles getting things to work and saving the TX profile and switching on and off a couple of times fixed that.

So as noted by WU2O the transverter range appears to be anthing you want it to be as long as its somewhere in the HF bands I.E. 1 - 60 MHz.

Bob


Thanks for posting back your results. I have been looking into and trying to learn about transverters lately for my 800DLE. Was also concerned that 432-438 was all that would be accessible which is an obvious issue since I am trying to decide transverter or new dual bander for the shack. I wanted the SSB capabilities and seamless integration of using my 8000DLE and not two radios but also need the ability to work 2M/440 repeaters. So with your reply above it looks like this really is not an issue and I can in fact do both on the 8000DLE

Nick
VK4BXI
Posts: 62
Joined: Sat May 22, 2021 11:44 am
Location: Brisbane

Re: Transverter range

Postby VK4BXI » Sat Feb 05, 2022 9:47 pm

Nick you are most welcome. I used a "Ukraine" transvertor. This had buttons to switch to switch from 2M to 70CM and to change the Lo frequency up by 2 MHz to help band coverage. All worked very well ......as advertised with exellent noise and sensitivity. As above you don't need to use the 2MHz button to get the extra range, but having to push the button to change from 2 to 70 and also switch bands in the 7000 very quickly became a royal pain. Not the least of having to stretch out for the button each time but having to remember to keep the two in synch. End result is that I added a relay inside the transvertor to do the switching. That was interesting to do ! The board was a multi layer board with alot of surface mount stuff.....very nice, but there were some sneaky submerged tracks associated with the band change switch. In the end I took the body of the band change switch apart, and was left with the switch pins going down into the board. I then wired in a very small double changeover 12 volt relay and took the coil out of the back of the box through a 3.5 mm audio jack and socket. I added a diode across the coil and drive the relay via the OC outputs of the Anan.
Moral of the story......use a single band transvertors and switch them in and out with coax relays or get a transvertor that can do relay driven band changes.....or be prepared to get you soldering iron out.

Regards Bob
N9SSW
Posts: 14
Joined: Sun Feb 24, 2019 10:25 am

Re: Transverter range

Postby N9SSW » Thu Feb 10, 2022 8:04 am

VK4BXI wrote:Nick you are most welcome. I used a "Ukraine" transvertor. This had buttons to switch to switch from 2M to 70CM and to change the Lo frequency up by 2 MHz to help band coverage. All worked very well ......as advertised with exellent noise and sensitivity. As above you don't need to use the 2MHz button to get the extra range, but having to push the button to change from 2 to 70 and also switch bands in the 7000 very quickly became a royal pain. Not the least of having to stretch out for the button each time but having to remember to keep the two in synch. End result is that I added a relay inside the transvertor to do the switching. That was interesting to do ! The board was a multi layer board with alot of surface mount stuff.....very nice, but there were some sneaky submerged tracks associated with the band change switch. In the end I took the body of the band change switch apart, and was left with the switch pins going down into the board. I then wired in a very small double changeover 12 volt relay and took the coil out of the back of the box through a 3.5 mm audio jack and socket. I added a diode across the coil and drive the relay via the OC outputs of the Anan.
Moral of the story......use a single band transvertors and switch them in and out with coax relays or get a transvertor that can do relay driven band changes.....or be prepared to get you soldering iron out.

Regards Bob



Thanks again Bob. I was looking at the Ukraine transverters... I am looking at this one which is currently out of stock https://www.ebay.com/itm/132503036008 With this transverter and a decent VHF\UHF amplifier I'm hoping to get some 2M/440 SSB experience as well as be capable of using the local 2M\440 repeaters on the 8000DLE. I don't mind getting out the soldering iron and I am betting I will likely put a bandswitch relay into the transverter box like you mention. I want to try to integrate as much as possible and make it seem like only the 8000DLE is doing it all and everything else is transparent.

Nick
VK4BXI
Posts: 62
Joined: Sat May 22, 2021 11:44 am
Location: Brisbane

Re: Transverter range

Postby VK4BXI » Thu Feb 10, 2022 8:42 am

yes that looks exactly like the one that I purchased.

regards Bob

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