Using one antenna?
Using one antenna?
Hi everyone,
I'm sure you have all conquered this little puzzle but I just don't see anyone talking about this or even documented on how it was done.
I want to use just one antenna with my Portsdown, i.e the Pluto. As the Pluto has separate RX / TX ports, what is everyone using to combine these ports so that just one antenna connection can be used?
Relays? Solid state RF Switch?
It would be most useful to see diagrams or photos of what others have used.
Many thanks
Matt
M0DQW
youtube.com/techmindsofficial
I'm sure you have all conquered this little puzzle but I just don't see anyone talking about this or even documented on how it was done.
I want to use just one antenna with my Portsdown, i.e the Pluto. As the Pluto has separate RX / TX ports, what is everyone using to combine these ports so that just one antenna connection can be used?
Relays? Solid state RF Switch?
It would be most useful to see diagrams or photos of what others have used.
Many thanks
Matt
M0DQW
youtube.com/techmindsofficial
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Re: Using one antenna?
Is this for Langstone use?? If yes, I fitted the extender board as shown on the Wiki, then used it to control a 12V SMA relay.
Plenty of de-coupling or the relay switching will promptly cause a Pluto disconnect/not found....
Gareth
Plenty of de-coupling or the relay switching will promptly cause a Pluto disconnect/not found....
Gareth
Re: Using one antenna?
Depending on the frequency range you need you could also use the BATC 2 way switch board. The RF switch chip is rated to 3GHz.
Colin.
Colin.
Re: Using one antenna?
Hi Matt
Like Gareth, I'm not sure what you are trying to do.
For the Portsdown with the Pluto, it only transmits. There is no Pluto receive (DATV or SSB/FM) functionality with the Portsdown and Pluto. An external MiniTiouner is required to receive DATV on the Portsdown. Clearly, this arrangement still needs aerial switching, so see below.
For Langstone (or Portsdown Pluto/MiniTiouner), I would highly recommend a relay switch. Normal miniature PCB relays are adequate for low powers at 144 and 432 MHz. Above that frequency it is worth looking for a specialist PCB RF relay, or a coaxial relay. Take a look at this Wiki page: https://wiki.batc.org.uk/Antennae_changeover_relays.
If you are using any sort of power amplifier on transmit, you will need to consider the isolation across the relay, so that you do not put too much of the transmit power into the Pluto receive port from leakage across the relay contacts.
Hope that helps
Dave, G8GKQ
Like Gareth, I'm not sure what you are trying to do.
For the Portsdown with the Pluto, it only transmits. There is no Pluto receive (DATV or SSB/FM) functionality with the Portsdown and Pluto. An external MiniTiouner is required to receive DATV on the Portsdown. Clearly, this arrangement still needs aerial switching, so see below.
For Langstone (or Portsdown Pluto/MiniTiouner), I would highly recommend a relay switch. Normal miniature PCB relays are adequate for low powers at 144 and 432 MHz. Above that frequency it is worth looking for a specialist PCB RF relay, or a coaxial relay. Take a look at this Wiki page: https://wiki.batc.org.uk/Antennae_changeover_relays.
If you are using any sort of power amplifier on transmit, you will need to consider the isolation across the relay, so that you do not put too much of the transmit power into the Pluto receive port from leakage across the relay contacts.
Hope that helps
Dave, G8GKQ
Re: Using one antenna?
Actually having separate Tx and Rx can be a benefit as it allows you to have a pre-amp AND FILTER in the rx leg and a PA and filter in the tx leg and combine them using a mechanical relay which is specified to at least your operating frequency.
Depending upon the frequency you should put the changeover relay and rx pre-amp at masthead and power them on receive with separate feeders for Tx and Rx - the Rx feeder can be satellite co-ax or similar as long as you put the pre-amp before it.
73
Noel - G8GTZ
Depending upon the frequency you should put the changeover relay and rx pre-amp at masthead and power them on receive with separate feeders for Tx and Rx - the Rx feeder can be satellite co-ax or similar as long as you put the pre-amp before it.
73
Noel - G8GTZ