Remote PTT for SGLabs Transverter
Posted: Wed Apr 10, 2019 10:34 pm
Hi, in an effort to maintain the ongoing life of Logger Forums, here is a small 'Show & Tell' contribution.
I recently completed my 13CM Spectrian amp upgrade based around an SGLabs transverter/FT817 and the 'PyroJoe' 30W amp board (eBay).
Big thanks to info from VK2.. VK3.. VK4.. VK5.. VK7.. etc who all had valuable info posted on this Forum of their 23/13/9CM etc. projects and tests to refer to for guidance.
I got the 12V, 30W version (actually 25W @ 2.4) going initially located in the shack with a 20 metre run of LMR400 to the 1M dish, mounted on my balcony. Lots of loss at 13CM.
In an effort to reduce coax loss, I decided to relocate the PA/Tvrtr unit closer to the dish. Mounting the PA box at the dish was not on. Mounting under the eve was possible, but it gets hammered with Wx from the west.
I compromised and mounted it just inside the lounge room wall, abt 3.5M coax from dish. The SGLabs transverter can operate from VOX which is fine at 2W, but not ideal driving a PA.
The SGLabs transverter can be internally selected for VOX, PTT or VTT to operate Tx. I already had it set for 'hard line' PTT in the shack, but needed to remotely PTT the PA.
By selecting VTT you can operate the SGLabs Tx remotely with +12V through the coax instead of running a 12V PTT cable to the PA box.
I found a 'cheap' Bias Tee on eBay that works a treat. The FT817 'ACC Mini Din' output plug gives you a (TX GND) pin closure to earth when you PTT.
I pick up a mini 12V relay and then send +12V through the Bias Tee to the SGLabs for PTT Tx.
73 Darrell vk2bls
I recently completed my 13CM Spectrian amp upgrade based around an SGLabs transverter/FT817 and the 'PyroJoe' 30W amp board (eBay).
Big thanks to info from VK2.. VK3.. VK4.. VK5.. VK7.. etc who all had valuable info posted on this Forum of their 23/13/9CM etc. projects and tests to refer to for guidance.
I got the 12V, 30W version (actually 25W @ 2.4) going initially located in the shack with a 20 metre run of LMR400 to the 1M dish, mounted on my balcony. Lots of loss at 13CM.
In an effort to reduce coax loss, I decided to relocate the PA/Tvrtr unit closer to the dish. Mounting the PA box at the dish was not on. Mounting under the eve was possible, but it gets hammered with Wx from the west.
I compromised and mounted it just inside the lounge room wall, abt 3.5M coax from dish. The SGLabs transverter can operate from VOX which is fine at 2W, but not ideal driving a PA.
The SGLabs transverter can be internally selected for VOX, PTT or VTT to operate Tx. I already had it set for 'hard line' PTT in the shack, but needed to remotely PTT the PA.
By selecting VTT you can operate the SGLabs Tx remotely with +12V through the coax instead of running a 12V PTT cable to the PA box.
I found a 'cheap' Bias Tee on eBay that works a treat. The FT817 'ACC Mini Din' output plug gives you a (TX GND) pin closure to earth when you PTT.
I pick up a mini 12V relay and then send +12V through the Bias Tee to the SGLabs for PTT Tx.
73 Darrell vk2bls