In the luxurious accommodations provided by Motel 8 and armed only with a few tools and a six pack – a pair of amateur radio enthusiasts attempted the repair of an old WWII era BC-224E receiver. They picked up the boat anchor antique receiver, which was in unknown condition, from a flea market while in town for the Dayton Hamvention, brought it back to their hotel and got to work.
The BC-224E came in two parts – the receiver and the power supply. The speaker for the system, which is actually located in the power supply, is driven by a large inductor. Apparently when the receiver was constructed, the permanent magnets of the day were not powerful enough to drive a speaker.
Fortunately, the receiver also came with some schematics, allowing [Gregory] and his fellow radio enthusiast to reverse engineer the power supply. After a few tweaks and cap swaps, they crossed their fingers and plugged it in. Stay tuned to see what happened next.
[youtube http://www.youtube.com/watch?v=0g0dFVFTujw&w=560&h=315%5D
They can’t even wait til they get home lol. Way to go guys! Got an old radio I need to fix still, and yeah it can kill me if plugged in…RE it will be a pain as it’s a lot of “air-board” and old components. It’s on the backburner but you hate to have a broken radio laying around.
One man’s trash is another man’s treasure. I got a nice piece of trash myself at a flea market today. I picked up a twin of my favorite belt sander for $5.
Dayton! Hacker-heaven.
Next time you are in Dayton and its not Hamvention time you should check out Mendlesons in downtown Dayton
the first floor is restaurant equipment and practically a department store while the third floor has everything from motors (even some 100hp+ beasts), stepper motors, pumps, utility power transformers, Neon sign transformers, Pc fans, squirrel cage fans, florescent fixtures, variacs, hydraulic pumps / filters /cylinders etc, end mills on and on and on and on and a mind boggling amount of discreet components resistors caps transistors ICs LEDs relays humidity sensors gauges connectors wire pc parts ALL KINDS of stuff… The IC’s are generally older..
This place is pretty much the size of a city block so you can imagine just how much is packed into the place but you must see to believe!! :P They do offer a small amount of mail order stuff on their site for those that haven’t the means to travel to Dayton but don’t consider their website to be indicative of the vast selection you will see in person!!
MENDELSON’S LIQUIDATION OUTLET – http://www.meci.com
340 East First Street
Dayton OH 45402
1-800-344-4465
Retail – Monday – Saturday 8:30-5:00 EST
Customer Service – Monday – Friday 8:30-5:00 EST
No I’m not affiliated with Mendlesons any way shape or form, but Ive loved the place since I was old enough to go wander the aisles.
This is one thing you left out the room that is filled from floor to ceiling with old tunes. I love going there. I usually wonder around for and hour or more.
What do you wonder about, whilst listening to those old tunes?
He meant TUBES i’m sure.. they have a remarkable yet dwindling stock of NOS (New Old Stock) tubes as well :)
The loudspeaker magnet coil normally serves as the power supply smoothing choke.
Ian.
P.S. I would love to be able to visit the Dayton Hamvention. It is well known even here in the UK.
Yep. Permanent Magnet speakers were certainly around before the war, but electro-magnets were far more powerful and you also got to use it as a choke. A nice 2-for-1.
Super old school geek cool.
73 DE N2NLQ
This has happened at Dayton Hamvention every day for the past 20 years, This is not that special in any way.
One year my friends and I built a 2 meter repeater from separate parts we bought during the day in a tent at the KOA campground, something a lot harder than repairing a older radio. we then used that 2 meter repeater for the rest of the event. yes we even erected a 40′ tower on the campsite.
I saw a guy one year completely assemble an Altair 8080 on a picnic table over the course of 3 days as he bought the random parts, he found the stripped altair on the first day. he was even doing component level stuff on the picnic table.
This is NORMAL for the Dayton Hamvention, although it’s a shadow of what it was back in the 90’s. the event used to be large enough that you could not see all of it in 3 days.
Just because it’s “normal” for the Dayton Hamvention does not preclude from it being remarkable anwhere/anytime else. Normal or not, it’s interesting, especially to hams like me that can’t get to Dayton.
I wish I didn’t live in “health and safety” UK. I cannot even recycle stuff from a dump. And the last time I found a place like Mendelsons the stuff was hugely over priced.
there is a good pace for radio stuff in lincoln on steep hill i forget what it is called
aren’t all the hills in Lincoln steep? Remember delivering beer there in a knackered old transit and having to take a serious run up to to just to get up them.
That would be J. Birkett on The Strait. Yes, it is steep.
I’m the guy on camera as the video opens, giving the crappy intro. We got the old signal corps radio working in the hotel that night, and I fixed the Hallicrafters rig a few months later. It currently sits atop my desk, next to my Icom IC-7410. Newer radios are feature-rich, but the tube rigs from this era have a sound and feel to them that you just can’t buy any more. There’s nothing like picking up Radio Havana on a radio that pre-dates the embargo, and knowing that you brought the old thing back to life.
You can learn a great deal about radio and RF design by working with old radios like this. Can actually touch each part, nothing is abstracted by integrated circuits or software. See this amazing youtube series from Bob Anderson to learn more: http://mrvacuumtube.blogspot.com/2011/10/bandersontvs-radio-101-youtube-series.html
Here’s my nit, it hardly seems like “Reverse Engineering” if you have a schematic.
I think he said in the video he had to reverse engineer the power supply and draw the schematic.
Only on the grounds that its “typical” for the Dayton Hamvention does not block from it being astounding anwhere/whenever else. Ordinary or not, its intriguing, particularly to hams like me that can’t get to Dayton.