any of you guys remember this?

I'm surprised that it ever worked.

That's so-o-o-o _modern_. My first build was an UltraLinear with Dynaco (?) transformer and 6L6's. ...Jim Thompson

Wimpy stuff. I built mine with a bucket load of color TV flyback driver tubes, direct mains rectification and _no_ output transformer. A few twangs on the E-guitar and plaster pieces came off the ceiling.

But I learned two lessons: High voltage DC at several amps is dangerous, threw me back against a cabinet and my shoulder put a crack in its door upon impact. Secondly, I will never ever attempt to rewind a speaker coil anymore, never no more.

I BET YOU ROCKED !!!!

I built mine in 1955. Were you even born yet ?:-)

In the mid '70's I was tutoring Algebra to a neighbor kid and offered a bribe, get an "A" and we'll build a guitar amplifier. He got the "A" and I built a 400W (true RMS rated) solid state amplifier. Transformer power supply... it took two people to carry it.

His father was president of Anthony Pools... so I also ended up with a swimming pool for half price ;-) ...Jim Thompson

It sure impressed the heck out of the guys but I could not play the guitar myself. Or any instrument for that matter. Still can't.

If you cranked it up too high, strum the strings .. THWOK .. circuit breaker popped. And that was on a 230V 16amp circuit.

Not even conceived :-)

I bet that has lit up many sessions for his band. 400W sustained is pretty good.

You should have gone into politics. That's how things work there, favors against favors :-)

A friend of mine was one of the founders and I worked at G.A.S. on and off from its beginning to its end. I built the first Ampzilla prototype kit to see if the parts and assembly manual were correct. They were and that amplifier probably still works.

The philosophy of the lead designers (Bongiorno and Hefley) was to create as-near-as-possible perfect voltage source amplifiers. Their biggest amp, Godzilla, would do 1KW into 2 ohms per channel. It really was a beast.

When G.A.S. was still selling kits, we received two driver boards back for repair that someone had built. Whoever built them had installed all of the resistors and capacitors by inserting the parts only far enough to be able to solder the leads. All of the parts were sticking off the board and high up in the air. It was hilarious! We sent him a pair tested production boards and kept his to show off.

It was a great company - while it lasted.

Bob

Yep. I was glad when they moved away to Arlington, VA. He would practice in their carport... you could hear it for miles :-(

When the depression hits, that's the way _all_ business will be done. No skill or trade, you die... gonna be really hard on unskilled liberals. ...Jim Thompson

It must have been like a 2000 VA transformer, right? What did something like that cost back then? Unfortunately for most DIYers it's nowadays probably cheaper to buy a 400 watt Class D amp off the shelf than buy iron for a class AB linear amp at that power level.

I really don't remember now. I certainly wasn't well-to-do back then, so it couldn't have been very much. I vaguely remember using two transformers, one for the plus supply and one for the minus. I also ran fans on the heat sinks ;-) ...Jim Thompson

He's an amateur. WLW had a plate modulate 500 kW AM transmitter at

I think that it was published in Popular Electronics, to sell kits.

That could be. Like most everything I've done, I didn't realize they would become valuable antiques (like me :-), so I tossed them in favor of "modern"... and didn't even take pictures :-( ...Jim Thompson

You are smart enough to know that you can't keep everything. Where would you keep it, if you did? :)

And then the license was revoked and they had to throttle power back down. My license wasn't revoked :-)

While I was in NY for three months my wife decided to "neaten up" my office. I'm just now getting back to my "indexed mess" so I can find everything ;-) ...Jim Thompson

idea

NEVER leave your wife alone with your toys!!!

Sigh. It was an experimental license that lapsed, after years of commercial testing & use. Powel Crosley was a defense contractor, and had lots of friends in Washington DC. A lot of other stations wanted to go to 500 KW, or higher. The idea was to provide AM radio to areas that didn't have or couldn't support a local station. Large areas of the country still had no radio reception at all, unlike today. WLW was the only US AM BCB station that was allowed to actually build and test the only 'Superpower AM' station. And they never tripped a breaker.

Considering that it operated in the '30s, it used more power than some small towns at that time.

There is some information on the WLW site, and Jim Hawkins site has more. They ran their original 50 KW transmitter for Y2K, instead of one of the newer transmitters that are normally used. OTOH, they used new parts, and the three companies involved built a well designed, state of the art facility. There were no sweep tubes at that time, so you wouldn't have built anything from scrap, anyway.