Small bench power supply for Transistor radios

I got really bored yesterday so I built an adjustable regulated power supply based on the schematic I posted.

I had been using batteries and battery packs with clip leads to power transistor radios so I needed to build this anyways.

I have a Lambda LP-532-FM Adjustable 40 volt 3 amp regulated power supply, but it is way to big and heavy for my bench.

So I built this:

I built it in about 5 hours from stuff I had floating around my shop:
A project case.
rubber feet.
old power cord and strain relief.
A transformer that outputs 28vac.
15 volt dc meter.
2 amp bridge rectifier pulled from some electronic device.
2200uf 50v electrolytic cap.
.1uf 50v film cap.
120 ohm resistor.
5k pot (I did not have a 3k).
LM317T adjustable voltage regulator.
heat sink.
Perf board.
Neon lamp.
fuse holder.
1 amp fuse on the output side of the transformer.
old SPST power switch.
1 tie point.
Some terminals.
There is still room for a milliamp meter.
There is a jumper so I can hook in my DMM as a milliamp meter.

The maximum voltage output is about 35 volts but I will not be using it over 12 volts. The el cheapo DC volt meter is pretty accurate.

I checked the heat sink last night while powering my Ray Jefferson 630rdf and noted that it was indeed too small. I rectified that problem but then broke a lead on the LM317T and had to get a new one this morning.

I think the new heat sink should be more than adequate, no?
I mounted the LM317T to the heatsink with non conductive thermal material (otherwise the case would have DC voltage on it) it seems to be working fine and not getting hot.

Here is the Schematic:

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