Weird Pan 42PV500 Problem - Can't Receive Some Freeview Channels When VCR Is On

[Kevo]

This one has been bugging me since I bought the Pan 42 PV500 back in late November.....

Initially I could get all Freeview channels OK, but after about a month I couldn't receive C5, BBC4 and QVC.

I assumed it was a problem with the reception, aeriel or even the latest firmware on the TV. As I could get all the channels on my PVR it didn't bother me too much, just a minor inconvenience.
But I couldn't understand why I could receive them OK on the PVR but not on the TV, as they were both on the same aeriel.

The plot thickens....

Anyway yesterday I received a DVB update and all the channels came back on the TV..great I thought until today where the said channels dissapeared again!

Well it turns out it wasn't the firmware or recption it was my VCR!!

Everytime I turn it on I lose the three channels. Turn it off and they appear.
It has been switched on all this time, even though I hardly use it these days.
The other day I decided to turn it off which coincided with th eday of the latest DVD update, so naturally I thought the update had fixed it!
Well today I was using the VCR and off went the channels.

I suppose it's the obvious weak link in the chain (that or the DVDRec) as the aeriel goes into the PVR first, then the HD/DVD Recorder, then the VCR and finally the TV, which explains why the PVR was OK. I was going to try and connect the aeriel direct to the TV a while back but didn't fancy battling with the spaghetti in the tight space behind the TV.

Question is....

Why do the three channels dissapear when I turn the VCR on?
Is the vcr tuner affecting a whole MUX?

 

[MAW]

It's the weakest mux, simple as that. You need to feed your aerial into a signal amp/distributor instead of daisy chaining. After all, you never watch any of these devices by RF on the plasma do you?

 

[Kevo]

Thanks MAW

No I never watch the RF on the plasma (apart from the odd teletext page) and a dist amp would probably be a better option. I just assumed the RF would reach the plasma on the daisy chain link unaffected.

Cheers.

 

[MAW]

It's all the connections that do it, you've got a lot of them!

 

[shugg]

hi there, mine's seems to be co-channel interference. when i turn on the pvr BBC2 from rf feed is always worse. Also i think the co-channel interference affects the pvr (a dhd4000) and i lose some channels on it too. I've just ordered a belkin power supply protector, which will help in general and possibly with this.
Currently my feed is rf to dhd4000 to vcr to plasma, and i have been lazy and not got a long scart to connect dhd to plasma and to complicate things further i need the vcr as the dhd doesn't pick up all the channels. any ideas out there shugg

 

[MAW]

Somewhere in the menu you'll be able to change the rf out channel. Toppys come set to 36, which is in use where I live, you just reset it to 63 or something up there. I'm assuming Kevo has sussed this, cos of course that could also be his problem, that the VCR is 'transmitting' on the same frequency as the Ch5 mux. But he's still got an awful lot of connections, and that would solve the problem in any case. Some VCRs you can't change the rf channel.

 

[Kevo]

Must admit I haven't checked the RF out channel on the VCR. I'm pretty sure it's adjustable via the menu
(not like the old days with a jewellers screw driver adjusting a tiny screw head round the back!).
I know I have a lot of RF connections daisy chained but in the past when they were all connected in the same way but to an anolgue only TV, then it wasn't really an issue as the RF was only really used up to the first device in the chain, the PVR. after that it was all SCARTS.
But now as the RF chain is needed right through to the Freeview TV, it has obviously show up a flaw in the chain.

 

[rayferry]

Your RF output from the VCR is set to the same or very close to the RF output channel of the MUX and must be moved. Have a look in your VCR's manual about changing the RF ouput channel, on most recent VCR's this in the menu system but on older ones it was a small screw on the top of the RF modulator.
Ideally normally setting the output to one end of the UHF band does the trick 21-25 or 65-68. The UHF band is getting very congested with analogue and digital transmissions coexsiting there are only 48 available UHF channels available between 21 and 68, a typical transmitter will have 5 analogue channels and 6 digital MUX's after that we need to find free channels for RF outputs from your VCR, PVR and HD/DVD Recorder if they all have one. You cannot also set all your equipment next to one another in band ie. 21, 22, 23, you would have to space them out ie. 21, 23, 25. This is because of sidebands from the RF modulators taking more bandwidth than the original output channel.

 

[shugg]

thanks for the gen chaps, i've turned off the rf feed from the pvr and that fixed bbc2 but then the vcr interfered with bbc1 I shall adjust its rf output now so all should be well shugg

 

[Kevo]

I've adjusted the RF out channel on my VCR and all the Freeview channels are working on my TV now (with ethe VCR switched on or off).
Channel 36 seemed to be ok as far as analog channels go in my region.