12/28/2013

Archer StereoDyne/3 Amplifier Clone

I was interested in building a small single ended amplifier, and found several that had been sold in the 60's. They went for quite a bit on ebay and I figured I would build one.

The amp in question was sold under several names and may have all used the same or similar design. The amps were sold under these names:
Archer StereoDyne/3
Truetest stereo/8
Monarch SA-10

I found this in an online copy of a Radio Shack Catalog.
I had found a stainless steel drawer at Goodwill. I had to order a couple of Edcor XSE15-8-2.5K audio output transformers, which took 6 weeks to ship. I had most of the other parts and only had to order some POT's and 3 meg resistors.

I designed the Layout of the amp in Autocad 2002. I then printed the drawings at 1:1 and taped them to the drawer.

 Center punched and drilled the holes.

Attached all the hardware, switches and pots.



 Then soldered in all the components.
There was some problems with hum and it took a couple of days to troubleshoot with help from an Antique Radio Forum.This is the original Schematic.
Here is the Final Schematic.
These are the pics of the finished amp. It still needs labels and better knobs.

Changes from the original design:
Added Isolation power Transformer to prevent accidental electrocution.
Better Audio output transformers.
Power indicator light.
3 prong plug grounded to chassis.
2 Channel input.
Fuses on input and output side of power transformer.
Used shielded cable for all the input wiring up to the 12ax7.
Added a 100uf Capacitor after first filter to reduce ripple by half.
Added a 22uf capacitor off of 125v source to pin 1 of both 35c5's to cancel out hum.
Removed "tone control".
Removed Stereo/Mono switch.

Hum is now down to 20 millivolts and can only be heard with your ears about 6 inches from the speakers.

This is a 1.5 watt per channel max, single ended tube amplifier. It will drive most any speakers just fine, frequency response is approximately 70 to 17000hz Not Hi-Fi, but 99% of the population can't tell. It will not do much in the way of deep bass, but bass is over-rated anyways.

12/26/2013

No Fuss "Lasagna"

Prep time 30 minutes.
Bake time 30 to 45 minutes or until cheese on top starts to brown.


Ingredients
1 - pound Italian sausage
1 - onion chapped
2 - cloves garlic chopped
1 - 12 oz bag egg noodles
2 - small cans mushrooms (or 2 cups fresh sliced)
16oz - Ricotta
2 - eggs
Italian Seasoning
Salt
Pepper
2 tablespoons butter (not margarine YA PANZY!)
2 - 32 ounce jars spaghetti sauce (your choice)
1 pound mozzarella cheese grated.

Heat Oven to 350 degrees.


To cut recipe in half , use half the noodles, and 1 jar spaghetti sauce.

Boil noodles 4 minutes (you read that right).

Don't worry about exact measurements or amounts, feel free to skimp on ingredients that you think are bad for you (or you don't like), but don't blame me if it doesn't turn out good (WUSS!).

Cook chopped onions in butter with 1 tsp salt, and 1 tsp pepper until slightly translucent. Brown Italian Sausage with 1 tsp Italian Seasoning, 1 clove garlic, add mushrooms towards the end.

While browning sausage, add 1 chopped clove garlic, 2 eggs, and 1 tsp Italian seasoning to Ricotta cheese. Whisk together.

Drain noodles, add (everything) both jars spaghetti sauce, sausage, onions, mushrooms, and ricotta cheese mixture to large pot and mix together carefully.

Dump in to one large lasagna pan or 2 or 3 9x13 inch pans. Top with grated mozzarella, and bake as noted above.

Remove from oven and let cool 15 minutes.

12/11/2013

Knight Signal Tracer

Picked this up at hamfest Saturday for $15. it does not have the probe and I will be making one.

Before




I did a simple recap on it, which reduced the noise levels on the (non noise setting). I replaced the cord, mic connector, and added a fuse. I removed the nasty stained speaker grill and replaced it with some black speaker cloth and a box fan guard. I then gave it a lite bath.

The 6E5 Eye tube seems a little dim and I will look for a replacement at some point.

After