I have an old RCA and GE transistor radio that use the 4 volt battery. Is there a battery available, and if so where do I find them? If not do these great old radios just lie dormant forever? I hope not. Jim W4KBD

A four volt battery would be something! Unless it used two cells of lead-acid type of construction. But you are talking a transistor radio here so that is ruled out. Small batteries come in increments of either 1.2 volts or 1.5 volts, depending on the type of battery, ni-cad, mercury, carbon-zinc, alkaline, or whatever.

See if you can come up with the battery type number and we can look it up and see exactly what it was and maybe a possible modern day replacement. Just saying it is a 4 volt battery does not mean much, as there were probably about a dozen different types of nine volt batteries that were in use once upon a time.
Curt

If its the one I'm thinking about....I've hacked up some "9 volt" batteries and found a little stack of 1.5 volt cylindrical cells. Tack three of those in series and wrap them with a piece of tape and voilá. 4.5 v battery that fits. Works in a little RCA transistor that I have, anyway.

Would a Lithium battery at 3.6 be too low a voltage to try?

Regarding 4.0 Volt batteries. On the early US models that originally used Mercury Cells like the Emerson Hybrids, All transistor types like Magnavox AM2s, GE P776, Philco, T3 (This Model Only used a 3 volts Line!! or 2 x Pen Cells to power), you can simply wire 3xAAs or AAA penlights in series if it will fit. For Japanese late '50s or early 60s models, you might have to try 3 x AAAs or perhaps 3 AAAAs. I have never had a problem using 4.5 Volts in lieu of a 4.0 v line. Because even though the schematics (Particularly SAMS Photofact) which indicate 4 volts, I believe they were probably slightly higher in voltage - current capacity of the cells is more relevant for long term performance of the radio.

Regards,

JP

More info on 4.0 Volt Battery.........Yes, many of these radios just stare back at the owners. However, any of them can be brought back to life- Some by only changing a few caps and getting another battery (with close to the right voltage) to fit. A few percentage of them can be more involved with multiple issues. However, the types of batteries that were required over 50 years ago are no longer available - but alternatives exist.... with the dizzing array of digital devices today, some interesting cells can be purchased. You can build just about any of them. Here's a site that I sometime purchase 'special' batteries from. However, some of these batteries can cost more than an old transistor radio. That's why I typically build my own cells unless you need a high voltage in a small space (Like 21.5 volt for the Regency, etc.). However, these are the exceptions not the rules for transistor radios.

http://www.batterycountry.com/ShopSite/ ... -cell.html


Regards,

JP

It still would be interesting if we knew the NEDA type number of the battery it called for. That way we could give a definate answer instead of beating all around the bush.
Curt

Hopefully the Model of the radio(s) are known. The battery type, label from back, or schematic would be preferred.


JP

Well, an example can be found with the RCA 1-TP-1. Beitman's 1961 for the schematic. It calls it a 4.0 volt battery, #VS149 would be the RCA battery number.

RCA Victor 1-TP-1HE is powered by a 4V battery, a size of AA or S-14 cell. These batteries are no longer available. I purchased a generic Sony camcorder LiIon NP-FP50 battery on ebay for $6. The battery is built of two 3.7V cells. The capacity is 900mAh. I soldered a small extension connector /please see the picture/ to the negative terminal of the cell to make it exactly the same size as AA/S-14/ cell. I charged it in a LiIon battery charger. NiCad and NiMH battery chargers are no suitable. The fully charged cell has 4 volts and with its huge capacity will power the radio for many hours. LiIon batteries do not self- discharge easily. Unlike NiCads. Greetings to all, Joe.

Yea Joe, that's what I had in mind!

And to answer your question, if the voltage of the fully charged LiIon cell dropped to 3.6V, the work of the radio /built on germanium transistors/ should still be quite stable. The old chemistry 4V batteries from the sixties did not hold their initial voltage too long and they did work. Their voltage dropped much more easily than LiIon for sure.-I have just checked the radio and it drains about 15 mA. Theoretically the LiIon cell should provide about 60 hours of work or more depending on how loud you play the radio. One may leave it inside the radio for a very long time.

Very good solution Joe. Anytime you can get a Secondary battery in a small space like with ample current and for a great price - go for it. It's probably not worth trying to come up with 4.0-4.5 volts via 3 AAAA primary batteries to fit in this space. I doubt the current capacity would be enough anyway. I have a Magnavox AM2 arriving this week and I'll probably need something like this or perhaps paralleling two of these 3.7 volt batteries?. Although, the footprint was quite a bit larger on the Magnavox than on the these Japanese built - American labeled radios. So I may have other options.

Best,

JP

Congratulations! Magnavox AM2 is a very pretty vintage radio from 1956. It employed Eveready mercury E233 4V battery and its capacity was smaller than todays LiIon 3.7V cell. Well, that was the technology from before half a century. Anyway connecting 2 cells in parallel will not hurt. It will increase the capacity and life and the voltage will not drop very easily. And this is something old electronic circuits built with germanium transistors did not like. Joe.

Curt: The NEDA number is 1304 for the RCA VS-149 (E-133) 4.2 volts. The The E-233 battery mentioned has a NEDA # 1300 - 4.035 volts. Allied lists a battery replacement for TR-133 (VS-149) for $5.17

Hey Jim, Could you please provide a link to the Mouser page for this battery? Thanks, Jim W4KBD

Use two 1.5 volt batteries with a 1N400x in series. Lots cheaper than a lithium ion.

Two 1.5V batteries and 1N400x in series will give about 2V output. I do not know what you mean. And what batteries for the tiny RCA radio battery compartment assuming that you meant 3 cells? I still do not understand.

I combed through the Mouser website and the 4" thick catalog and couldn't find them. But I did find several on-line battery sellers offering the NEDA 1304 for about $12 each (free shipping!) All of them listed it at 4.5 volts. Googling NEDA 1300 turned up nothing.

Dave

Sorry about the confusion, my mistake! The battery is in the Allied catalog. 2006, page 692, Daytona Industries, Allied number #774-0182 TR-133A, $5.17 each, 4.5 volts 650ma. Cross ref: E133, PC133A, TR133A, EN133, A133, 3LR50.