I love nothing better than to do some AM DX'ing at night time with a 1960's transistor radio with a RF stage. I have even picked up 2YA, 567 kHz, Wellington, NZ, here in inner Melbourne.

I agree with Brad about the quality of digital broadcasts. I work directly above a busy railway line. AM reception there is very poor due to interference from the trains and overhead wires. Some of the guys at work won a substantial lottery prize and shouted the office a digital radio. The digital reception is unhindered by all the electrical crud that surrounds us there.

Here are some 1949 &1950 Healing Christmas ad's from the Womens Weekly:

http://trove.nla.gov.au/ndp/imageservice/nla.news-page4311813/print.
http://trove.nla.gov.au/ndp/imageservice/nla.news-page4780770/print.

Internet is virtually an extension of cable and that and similar works fine for fixed city installations where you can sit down, enjoy & appreciate. Country land lines like mine are struggling to handle normal phone calls.

Clearly someone is trying to make a lot of money forcing onto us duplicitous infrastructure of limited, if any value. Digital radio looks like it's going to be like mobile, limitations in the bush where you seem to need a repeater every Km.

Marc

Why does Channel 7 need to be on 7 and 71, for example?

Looking at the program guide, it seems broadcasters like to do that with sporting event coverage more than other types of programming.

If they show the same event on all channels I suppose they think it maximises audience reach (for advertising revenue) without their alternative channels robbing them of audience.

I don't know if regional reception issues apply to digital; that is if (say) 71 is easier to get in one area than 72.

Otherwise I guess the reason is that broadcasters don't have enough program material to transmit different shows on each of their channels simultaneously. And the alternatives of playing music with test pattern or shutting down the transmitters aren't considered viable options.

This is a timely topic.... I have had one of these units kicking around for decades, and literally have made the decision within the last couple of days to try and get it going.

I can't seem to find the definitive answers I require, so I wondered anyone here may know....

From what I have learnt from my research, and observed in the unit I have, it is a Healing Golden Voice, model 503b. It is a purely portable, battery operated (only) unit. There are two DC voltage supplies required (apparently) : 90v and 1.5v.

Originally this unit would have had two and three pin type plugs that designated the different supply voltages/ batteries. Unfortunately in the case of the unit I have, someone has removed all plugs and all that is left is four different coloured wires that disappear into the back of the chassis : black, orange, blue (could be green), white....

It looks like the black/ orange are the low voltage supply and the blue/white are the high voltage supply (Please confirm??) If this is so, what are the polarity designations for the different colours?

This radio used to be my grandpa's, and given that he died in 1973, means this unit hasn't been powered up for at least 40 years!! I've always dreamt of bringing it back to life.

Any help would be highly appreciated.

Thanks.

Jamie Scholar: Any help would be highly appreciated.

For the schematic and service notes, click this link:

http://www.kevinchant.com/uploads/7/1/0/8/7108231/503b.pdf.

Wire colours are not given, but you should be able to identify them with the aid of the schematic.

QUOTE: Where I used to live even with the best aerial I could buy and much experimentation with aiming etc still ended up with pixelated pictures from time to time.

My neighbours had the same experience and they to spent money on new aerials.

...

Has USA, UK and Europe adopted digital radio?

And I thought we had problems with the 8VSB transmission method the USA selected over COFDM.

We do have digital radio, using "In Band On Channel" IBOC. On AM, you can find stations with IBOC as you hear hash just above and below the analogue signal. FM is more discreet, FM demodulators ignore it completely. Almost noone has bought it.

Almost noone has bought it.

In the US it'll be a costly changeover. I'm told there's something like 13,000 radio stations there.

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A valve a day keeps the transistor away...