I've been thinking, Why do I need a speaker hooked up, just to see if the unit powers up?
How else are you going to tell if it powers up? You have to be able to at least hear some static.
Here's the deal with speaker impedance (ohm rating). Most home stereo uses 4 ohm speakers, most original car radios use 8 ohm. In a perfect world, you use an 8 ohm speaker with your radio. If you just had two 4 ohm speakers, you could hook them in series and come up with 8 ohms. BTW, if you hook them in parallel, it drops to 2 ohms, but I digress.
So... The best way is about any car radio speaker to try your radio. I'll even say this, if you should only have a 4 ohm speaker, you could get away with trying it... Just don't run it very long or at high volume. It is best to use an 8 ohm speaker though.
That said, it's been my experience that a 50+ year old radio usually doesn't work very well and it would not surprise me at all if this powered up, played some music etc. and then either died after installing or the tuner and/or volume drifts so much that you have to adjust the radio every couple minutes. The radio in my 300L is like that. I've been sending radios to
Aurora FMR Stereo Conversion . Yea, not the cheapest option, but I think it's the best option. Two of my cars have Aurora converted radios and they work great. My 300L radio will get shipped down there when the snow flies.
