Zenith RD7000

[lken37]

I just purchased an very nice RD700 Transocianic running on batteries. A card added by someone says the radio is set up for 220 volts, and that it is easy to change to 120 but doesn't say how. Will it damage if I purchase a R7000 power cord and just plug it in?
Thanks.
Ken

 

[K4EET]

Hi Ken @lken37 and welcome since this looks like your first post.

Do not plug it in to an incorrect supply voltage!!!

Is this what you have:

1970's Zenith Transoceanic Model RD7000Y 11 Band FM AM Radio

wd4eui.com

It is a Transoceanic but has a slightly different model number. If that is not your receiver, please post as much information as you can and pictures will help too.

Many of those radios had a slide switch on the back side or in the battery compartment to switch the line voltage between 120 VAC and 220 VAC. The 220 VAC line voltage is found in many foreign countries. In the United States, you will generally find 240 VAC on the range/oven, hot water heater, heat pump and well pump (as needed) in all-electric homes.

With a little more information on what you have, we may be able to determine if there is a slide switch to change the line voltage.

Cheers! Dave K4EET

<edit> I see the title is correct. The text said RD700 which is what I was looking at… 🤓

 

[K4EET]

Hi Ken @lken37 and I misread the number of posts. I should not do these threads when I'm tired...

I found a schematic but it does not have the entire circuitry. It is missing the power supply portion among a few other key circuits.

Look closely where the AC power cord plugs in and see if there is a small, flat, rectangular, (maybe even red) slide switch marked 120 / 230. If you can find that switch (if there is one), then you can easily switch the receiver's line voltage back to 120 VAC.

 

[Boombox]

Run it on batteries. Transoceanics are famous for being easy on batteries. Power supplies can vary in output from the nominal voltage.

It's a classic radio. Don't chance it. Just my opinion.

And I have a 3000 Transoceanic and almost blew it up because I used the (proper) adaptor instead of just relying on batteries. I almost learned the hard way. The adaptor was putting out half again the voltage. Luckily, the output transistors merely shut down, instead of lighting up. And it still works now, so I keep it on batteries.

Other guys have done what I did and found themselves needing to source new output transistors. The 7000 may have more robust circuitry, but if the radio does well on batteries why chance it?

Personally, any portable -- even if it has an AC adaptor, I run on batteries.

 

[majoco]

Boombox says:

And I have a 3000 Transoceanic and almost blew it up because I used the (proper) adaptor instead of just relying on batteries.

The problem with the 3000-1 is that it draws very little current from an external adaptor - probably around 25mA. Most wall warts that supposedly supply 12volts actually go much higher on a light load and there are two capacitors on the external power socket that are rated at 12volts - if you give them 15volts or so they may well go pop. Zenith users - me included often use a 9 volt power adaptor.

 

[lken37]

Thank you folks tor helping me with this ne radio. Much appreciated