Early Admiral on Kijiji Toronto
 

http://ontario.kijiji.ca/c-buy-and-s...AdIdZ524161984

$450


TV - Antique (Vintage) - Vintage Retro or Mid Century Modern 1940's Admiral Bakelite TV; An original black and white floor model television; made by Canadian Admiral Corporation Ltd., Malton, Ontario. Dimensions are:16 in. wide, 32 in. tall, 18 in. deep; Model No. 24A12X; it is a 25 cycle television, but works on 60 cycle 117 volt AC; The front has a Horizontal/Vertical Adjstment Knob, a Contrast/Brightness knob, a Off/Volume/Focus knob, and a Channel/Sharp tuning settings Knob (this is the missing knob). The back has Vertical Line, Height, Horizontal Lock, Horizontal , Horizonatal Line and Horizontal Width settings. It has an original label intact.; No. 132400 CSA AFP No. 9720. It turns on, tubes light up; IT WORKS; Please call or text 905-687-2875.

I love the huge 25Hz transformer :) Here's the 60Hz version.

http://www.videokarma.org/attachment...7&d=1379384944 http://farm5.staticflickr.com/4071/4...0f216d1b4d.jpg

Wow, that would make the 25 Hz version another 15 lbs heavier!

I had never heard of 25-cycle power. I don't think even a restored one of these would go for that much. That transformer is something else though. Imagine dropping that on your foot.

Fishing expedition.

All of Canada had 25 cycle power, as opposed to 60 cycle, until the mid-60s or so IIRC. I had a CTC-5 with an outboard transformer setup that was made to handle 25 cycle power....it was bought in the US and transported over.

You can use 25 cycle stuff on 60 cycle current, but not the other way around.

Definitely not all of Canada had 25 Hz in 1960. Some regions did have
it until the mid sixties as you say, but I believe for instance that Montreal
never had anything other than 60 Hz once AC power became available.
I do have a Motorola clock radio (with AA5 electronics) designed for
25 Hz. Have been thinking of building a 60-to-25 Hz converter just to
run that radio, but it remains a project.

You don't have to build a converter. Just plug it in. Being in Buffalo, we get quite a few radios from Canada that come this way that have 25 hz transformers.

The radio has double filtering for 25 HZ. It's a regular AC/DC type AA5 with an electric clock.
The rotor will have to be replaced in the clock, as it will run really fast.

Because the TV is 25hz, will it consume more power or less ?

Maybe a tiny bit more due to the losses in extra filter capacitors, but
should probably be insignificant.

Regarding my earlier post, there is the obvious problem with the
clock. Some people have told me that a 25 Hz clock powered at
60 Hz will run really fast, others that it will not run at all. Of course
the clock may not be in working order in the first place.

AC operated clock motors are a synchronous design and are frequency sensitive. That's the reason, that electric clocks are so accurate.
Telechron built clocks for 25,40,50 and 60hz. The rotors had all different gear ratios.

Can you imagine the Flicker of light bulbs at 25 Hz?

Got to get a rotor for my Telechron oddity. Never knew those depended on the pulse of the AC line.
No, but I would like to see it.

Has anybody actually seen the flicker at 25 Hz with incandescent bulbs? With
a powerful hi-fi amp and an audio generator, you could do some experiments.
I would not expect that 50 Hz flicker to be perceptible (don't forget there are
two zero crossings per cycle).

I can just start to perceive flicker at 30hz using a sine wave on an LED. But the LED is only seeing half cycles. I doubt my eyes would see any flicker in an incandescent at 25hz.

I've seen it. Back in the early 60's, parts of the New York City subway system used 25Hz. Their light bulbs lighting the stations did flicker. An oddity of the human eye is that the brighter the light source is, the higher the frequency you need to avoid the perception of flicker goes up. The rest of the station didn't seem to flicker as much as the bare bulbs themselves did. As the rest of the station hits your retina as a lower bightness level. Also 3 phases of electric supply would also smooth things out.

You also see this effect on 50Hz TV displays (PAL) vs 60Hz (NTSC) at higher brightness settings on CRTs.

A power transformer designed for 120V@25Hz in theory will be happy at 240V@60Hz. All the secondary voltages will be twice the rated voltages. One limitation is how good the insulation is on the secondary used to make B+.

Absolutely.
This was in Roosevelt, AZ in the 60s and early 70s, during visits to the local bait & tackle store. The bulbs i saw were clear glass, dunno if the flicker woulda been diminished any if they had been frosted glass.
Conversion to 60 cycle didn't come until 1973. Here's a bit of skinny on the frequency standardizarion project..
https://www.srpnet.com/gallery/trd/1971.aspx

Some may recall my RCA CTC5 bought in Toronto was converted in Montreal for 25 Hz power. It had a separate chassis added underneath which sported a heavy B supply transformer and the original chassis mounted transformer was changed for filaments only. The modigivcation added about another 25 pounds to an already heavy set.

Old timers including my Dad remembered the flickering bulbs. Interestinglyly people got used to it: my Dad emigrated to Canada in 1948 and he said the flickering lamps in Toronto initially gave him a headache. But after a few months he got used to it. Note that even though the frequency is 25Hz, the bulb flicker rate was 50 Hz.

I believe Toronto switched to 60Hz around 1958 when there was a major 25Hz generator failure.

Incidently the Tesla standard was 60Hz and he had to face opposition at Niagara when the engineers there wanted 16Hz. The compromise was reached at 25Hz in 1893. The last 25 Hz William Rankine generation at Niagara closed only in 2009.

Terry

Amtrak's Northeast Corridor is still 25hz below the phase break on the Hell Gate bridge approach. I remember in college seeing E60's in Penn Station, and yes, their number boards and all had a noticeable flicker to them. HEP is 60Hz, but I suspect there's a strong 25hz harmonic riding on it because you can see a slight flicker on older Amfleet cars once you change from 60Hz to 25Hz power.
They convert it at a few places, notably Metuchen, NJ. I have an article on SEPTA's 25Hz converter at Wayne Junction - ASEA built it in the late 80's and it was quite an interesting beast. Even today, listen closely to a SEPTA regional train, and you can hear a slight rumbling as they pull out of the station.

16 2/3rds is still a standard frequency for RR traction in Germany, Austria, Switzerland, Sweden, and a few other countries. 25Hz became the standard in the US and is still used (see above post)

:oOOPs! Duplicate post.