- This topic has 6 replies, 3 voices, and was last updated 2 years, 9 months ago by
.
-
Posts
-
Today I picked up an FVP 5000T for almost nothing at a boot sale and have tested it for WiFi operation and recordings etc and everything seems to work fine.
I currently have a very old Humax box with external hard drive that works fine but only has the one channel, no Freeview Play or WiFi, so it would be a significant upgrade to use the new one.
The only problem I have is that I have a loft antenna that uses a 5 vdc masthead amplifier that is powered up by the old Humax using the “Antenna Power” option in the settings menu and it works very well, sending the 5 vdc up the coaxial cable to the amplifier in the loft.
Unfortunately, the PVR 5000T doesn’t have this “Antenna Power” option, and as I don’t have a 240 volt feed to the loft, it’s a bit of problem working out how to get the 5dc up into the loft.
It did occur to me that I could rig up a 5vdc supply and tap that into the coax down by the Humax, but I’m not sure if that would cause a problem with the PVR as it would now be getting a 5vdc feed into the signal input connection that it wasn’t generating itself, unlike the old Humax which is … If you see what mean.
I am keen to keep the masthead option as the 1970s vintage coax is stuck in the wall cavity and loses so much signal that trying to amplify the weak signal at the TV end doesn’t work well.
Any advice would be gratefully accepted. Thanks.
You may be able find a 5V masthead amp power supply from various souces. But it may be easier to buy a complete kit, new amplifier and power supply, all the usual sources stock them. Just make sure they have standard aerial fittings, if not you will have to change the cable ends to F-Plugs.
Thanks for that.
Is a masthead PSU a specialised piece of kit that somehow separates the voltage and signals within and only sends the signal to the Humax box without the voltage that’s going up to the amplifier?
Yes it is, as it has to pass DC power and the Radio signal frequencies as you have worked out. It uses Inductors to pass DC power and block the signal and isolating capacitors to pass the signal and block DC power. these are carefully chosen.
Thank you for that.
I’ll check the voltage range on the amplifier and see if I can find a PSU to match.
The old Humax mentions that it supplies 5 volts, but it may be that the amplifier can take the more common 12 volts.
Much appreciated.
For the time being, just use both Humax and loop the antenna through both. That way your original box will be doing what it’s always done.
Or get one of these :-
https://www.screwfix.com/p/labgear-5a-f-plug-amplifier-power-supply-1-25m/80459
I did wonder about doing that, but in the past, I’ve found that the signal strength that comes out of the old Humax doesn’t seem to be anywhere near as strong as the signal it’s getting.
With the antenna power option switched off, it’s almost impossible to get any channels at all. Once it’s switched on, then every channel is available and perfect.
However, we have another TV in another room and I split the signal coming out of the Humax, with one lead going to the other TV and one going to the antenna port on the TV that the Humax is serving through the hdmi port.
In this case, I found that I needed another amplifier / splitter on the Humax out signal to give a good enough signal to both.
- You must be logged in to reply to this topic.