Faulty TV aerial distribution amplifier?

Andrew Gabriel wrote:

Beryllium.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
After serious thinking John Laird wrote :

That would indicate dry solder joints, rather than actual failed components. Most probably solder connection to the sockets.
There is almost nothing inside...
Power supply; basic amplifier; perhaps filter components and then some impendence matching to each output socket.
--

Regards,
Harry (M1BYT) (L)
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Very likely to be a lightning belt, this happened to ours a few weeks ago. Identical symptoms. Unless you can recognise the appropriate transistors then replacement is the only cure!.
Don't worry about it being in the loft, the one that did ours in hit a house 400 yards away!....
--
Tony Sayer


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
tony sayer explained :

Agreed, I had similar happen a few years ago. It took a printer, modem and an expensive satellite system out. Indoors only improves its chances of surviving, it will not guarantee it.
--

Regards,
Harry (M1BYT) (L)
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
tony sayer wrote:

A lightning strike anywhere within half a mile can induce a pretty massive voltage into any cable. You don't need a direct strike or anything LIKE it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Interesting! Thanks. Definitely going to try a replacement then.
--
Change red to blue in email address.



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
OK so I'm planning to buy a new TV distribution amplifier. Can I get a little help?
My existing one (assumed faulty) boasts a frequency range of 40-900MHz. Maplin have a 6-way and an 8-way model (nos YZ86T and KR20W), both with a frequency range of 47-230MHz.I've seen other models on ebay quoting near to the 900Mhz top end. a) is the much lower top end of the range on the Maplins a problem for TV signals? I'm afraid I've no idea whether it's important or not. b) the two Maplins models are the same price - is there any reason not to simply buy the 8-way one?
Any advice appreciated.
--
Change red to blue in email address.



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

You'd do best if you avoid one that covers around 170 MHz if you live anywhere near a main road. Most taxi radios operate around the 160-170MHz range; if they "key-up" anywhere near your sensitive amplifier you'll very likely get breakthrough, or at least overload of the amplifier causing all sorts of problems. If you want really reliable reception of _TV_ and aren't interested in FM or DAB reception via the same amplifier, get one which operates on UHF only.
--
Frank Erskine

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thanks for the reply. See my reply to the post above!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

That sounds like the FM range. It doesn't even get into the TV band, which would be a slight problem if it was indeed all the unit could manage ;-) A minute's Googling turned up the spec for the UHF range as 470-862MHz. That's fine.

Probably not. My own amp is looking a bit iffy, but I wasn't keen on what seemed to be the somewhat high gain quoted on the Maplin units - they claim 12dB per output. Fine if your signal is somewhat weak, but if you are distributing the signal (as I do) from the digibox and VCR chained together, then each of these has in turn typically added a small boost already. My Taylor unit says 2dB on it - it's basically just distributing and only amplifying in the sense that 8 outputs from 1 input does require amplification. There have been times when I have found a 6dB attenuator on the amp input has reduced some noticeable noise and visible artifacts.
--
For the words of the profits were written on the studio wall.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I wish I knew how you found that out in 1 minute's googling - I've hunted high and low and can't find it - any google tips?
Meanwhile I went to Maplins and bought a slightly different model (it's what they had in stock) the L24AG, which is one of those ones with a digital by-pass. Anyway, I've plugged it in and now my picture is near PERFECT on all TVs. So the old amplifier was faulty for whatever reason.
Incidentally, this model has a gain of 6dB on each output. I'm distributing the signal from the loft, near the aerial. I don't know about this digital by-pass thing as we have cable TV.
Thanks everybody for all the help.
--
Change red to blue in email address.



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I happened to know it was branded SLX (as I'd looked at them in my local maplin). Second link under "SLX 6-way amplifier specification" got me the info you needed. Always give Google a selection of words to go on. Specification was probably the key here.
I have Google's Toolbar loaded into IE and Firefox. Search engine is set to google.co.uk as this nicely pops up results with the additional "Search UK pages only" button. Not fool-proof, but pretty reliable.
When looking for prices, I usually add VAT into the search string.
Apart from that, practice is the key. I have misspent a lot of time online ;-)
--
Those who can't write, write manuals.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thanks. I think you were quite lucky with that one, though! Other search variants don't find that site.
I too use the Google toolbar in the way you do. Nice idea about VAT for prices.
The 6dB box I've bought is certainly doing the business for me, no idea whether 12dB gain would have caused any problems.
--
Change red to blue in email address.



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@redyonder.co.uk says... <snip>

Search for uhf-tv frequency-range on google.co.uk, selecting "pages from the UK"
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.