masthead amp needs Power Supply

[caveman]

Hi all Can anyone advise me to how to work out what Power Supply is required for a mast head amp i that i can't access easily

[Antennaman]

One suggestion is to take a picture of the amplifier if you have a digital camera with zoom function and link to the picture from here. That may help in identifying the animal.

Most masthead amplifiers that I come across use 22V AC. Some use 27V AC, others 17V AC/14V DC. If you cant find out, then a good starting point is to track down a Kingray PSK06 and use that. This is a 14V DC supply, which should run the majority of mastheads. Of course, if your particular amplifier is meant to run on a higher voltage, then at 14V it will have less gain, and therefore less output.

Unless you are in a critical area for TV reception, this may turn out to be of no consequence. I adopt this approach when some f***tard has put an amplifier at the top of a 10 metre mast and it is not easily identified. Why not drop the mast to find out? Not bloody likely, when the locking devices are nicely rusted, and likely to fracture when attempting to undo them, rendering a simple callout for the new owner of a house turning into an expensive repair exercise.

[caveman]

so there is no way of telling using a multimeter.I guess the cheapest option would be to buy a 14v dc supply and try that.I've found an old 22v ac supply if i try that can it do any damage or should i start with the 14v option .Thanks

[mtv]

You are taking a gamble.....

Ultimately, you need to be able to see the circuit board markings on the amplifier to identify the voltage requirements.

If you connect the wrong supply, you risk damaging the amp, so you will need to access the amp anyway, if you need to replace it.

Some 22VAC amps will also run on 24VDC supplies.

The most common ones I see are 17VAC 22VAC 12VDC

[caveman]

The big q?why ain't these things standardized?

it would make life a lot easier!

Anyway i think i better get someone who can drop this mast saftly as it above my skill level.

q2 as a rule does a new digital antenna need to be as high the 40 ft analog?

ones in our area don't seem to be as high

[Neutral]

I guess it depends on were you are but with digital tv they have a few more repeaters installed in variuos locations so generaly no they dont have be as high as the analog.
Forgot to ask what brand is the mast head.

[caveman]

By the color i would guess a kingray

[mtv]

as a rule does a new digital antenna need to be as high the 40 ft analog? ones in our area don't seem to be as high

Digital TV signals are an entirely different ball-game to analogue.

Additional height is not always going to provide better digital reception.

I have had plenty of installations where the best digital signals were obtained at lower heights than previously installed analogue antennas (on the same house).

With digital, even moving an antenna a few centimetres in any direction (incl up/down) can be the difference between reliable reception and no reception, especially in difficult reception areas.

The only way to determine the best mounting location for digital reception, is to have a site-test done, measuring the signal strength, and most importantly, signal 'quality' (BER MER NR)

With digital, amplifiers should only be used to compensate for signal losses in distribution (split to several outlets/long cable runs etc) not to boost poor signals. The key to reliable digital reception is selecting the correct antenna which will capture strong signals with low data errors and installing it in the 'sweet-spot'.

It's possble you may not even require your masthead amp with digital.

If you mention your area, this will help with advising what options you may have.

[Neutral]

By the color i would guess a kingray

The Kingray Brand are made by GME or Standard Communications, I used to work there a many years back they are in Gladesville sydney.



Have alook here & see if you can find your powersupply and let me know which one it is.



I'll get back to you regarding the PSU specs.

[mtv]

Have alook here & see if you can find your powersupply and let me know which one it is.

My understanding is he doesn't have a power supply (to look at). If he did, he wouldn't have a problem

[caveman]

We are in Terang , Western Victoria looking at the Lookout Hill Ballarat transmitter,and yes the mast head amp hasn't got a power supply,I guess the last tennant took it with them and the owner just shrugs his shouders.
I'm sure the antenna and masthead amp works alright as when we looked through property i took notice of the tv reception.
i'm also sure it a kingray by the color and shape compared with pitures on internet

[Antennaman]

By the color i would guess a kingray

I presume by that you mean it is the blue/gray colour of the amplifiers referred to in the link that neutral provided. Earlier versions of Kingrays were cream with a red lid.

All Kingray masthead amplifiers operate on ac, the difference is that later versions have a 17.5/22VAC strap. If you are absolutely sure it is a Kingray, you can try your old 22V plug-pak for a quick check, even if the masthead is strapped for 17.5.

Have come across installations using Hills 27VAC power supplies, and where the original amplifier has been replaced with a 22v operating one, where these replacements have been going for years. These include Kingrays, Alcads, Ikusis and others. Of course, the correct plug-pak is installed when this is discovered.

[caveman]

Yes its blue/grey in color I'll give it a try
I seem to remember something about trying it in all points because of splitters or something
let you know how it goes

[Antennaman]

the mast head amp hasn't got a power supply,I guess the last tennant took it with them and the owner just shrugs his shouders.

We come across this scenario regularly, so it might be in your best interest to argue that it is a non-urgent repair for a fixture to the property. In a lot of cases, exiting tenants unplug everything and take it when they go, and this includes the plug-pak.

This seems to be a grey area, as to whose responsibility it is to resolve, so plug your power supply in, if it doesn't work, then use page 18 of this guide:

http://www.consumer.vic.gov.au/CA256902000FE154/Lookup/CAV_Publications_Renting/$file/RentingComplete.pdf

which you should have anyway. Best of luck.

[caveman]

Back again plugged in 22v ac and zilch nothing oh except lots and lots of snow.
Thanks antennaman for consumer tip but my situation is i'm buying this house and only renting for another 12 days until settlement

[mtv]

caveman,

You are approx 110km from the Lookout Hill TX. a Band 5 or Band 4+ antenna horizontally polarised will provide the best results.

The alternative is Warrnambool, (Tower Hill TX site) 48km, requiring a Band 5 antenna vertically polarised.

The most suitable amp will be band 5 (or Band4/5 UHF) for both locations.

The antenna may have been installed prior to the Warrnambool translators coming online.

As mentioned, being a rental property, the owner/agent is responsible for ensuring all fixtures are working correctly.

A TV antenna/mast/amplifier etc is a fixture of the premises.

If the previous tenant has taken the power suppy (a common scenario) it's up to the owner/agent to sort out.

EDIT: See now you are buying the property... also, if you have more than one antenna outlet, only one outlet is probably configured to pass power to the amp, so try plugging the supply into each outlet.

[caveman]

Thank you every one who answered i"ve done a bit of climb in the ceiling looking for a splitter and found a beige junction box and plugged it into a extension lead.I knew instantly i'd found the problem when my lovely wife went crazy screaming and dancing around the house!I kid you not she loves tv more than me.Once again thanks for all your help

[mtv]

hehe... looks like you found the power supply.

A good outcome then.

[caveman]

yep i guess they just took the extension lead.A little embarrassed such a simple problem took so long to figure out.

[gordon_s1942]

I was trying to track down a Kingray 18V DC 2amp supply shown as a PAK something or other and would you believe that although it is on the Kingray website, the operator didnt know of it. Then I was told it was a 9V DC 2amp supply not an 18V etc and would you believe there is one listed as such in a suppliers Catalog along with a 60V job.
However nowhere in this catalog was shown any MHA's wanting 9V nor 60V.
I do have a Dick Smith Inline amp (never used) that apparently uses 9V.
I have a MHU 42 14V MHA along with a SAM 201? and 70 metres of RG6 and I had been getting advise to go from the PSK06 14 V 150 mA and pour some more kerosene intothe line to compensate for line loss.
I am running a voltage selectable power supply at 18 V DC 2 A into the injector and so far no flames or that magic 'Blue Smoke' has escaped.

Antennaman, that 27 V Hills MHA, was that the old Telstar range ?? Blue and white and sort of shoe shapped, 300 ohm ribbon ? ? they were the lifes blood used here for boosting from the mid 60's to well into the 80's.I think I still have one of the brochures for their use hidden away somewhere.
These heads were used on open line runs around the Lithgow area where the antenna (CA16 Hills Phased array) was mounted on the high ridge line and either bare or insulated copper wire ran down the slopes up to 500 feet to the house below.
Trouble was they were often pinched if anothers died from a lightning surge, cheap replacement.
Today all that is left is the odd length of mast cemented into an outcrop of rock.