Servicing a 1970s Magnavox 300 am/fm stereo receiver. part 1/3

Servicing a 1970s Magnavox 300 am/fm stereo receiver. part 1/3 - L-ch out

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Күн бұрын

No sound from the left channel. Only a dull hum. Happened suddenly.
Owner did some basic troubleshooting but was unable to discover the fault.
Lets see what's wrong!

Пікірлер: 33

@Synthematix 10 ай бұрын

Love the cherry red illumination, very nice

@jdpinbaytown 10 ай бұрын

Love that too!, It's actually mine!

@lox_501 10 ай бұрын

Another great video Jordan!

@radio-ged4626 10 ай бұрын

I've seen Magnavox tape decks and speakers, I've never seen a tuner or tuner/amp by them before. Looking forward to the pre-amp go-over. I know class A is usually not thought of as top end in the quality/performance steaks, but I like them - I think you get a lot for your money (or used to before the prices went mental).

@stirlingschmidt6325 10 ай бұрын

This goes to show how 'popular thought' is sometimes just wrong - properly designed class A amplifiers deliver the highest possible fidelity, since the amplifying device conducts over the entire cycle.

@radio-ged4626 10 ай бұрын

Yep.

@stirlingschmidt6325 10 ай бұрын

Thanks Jordan! Always good stuff...

@muddy32456 10 ай бұрын

true perspective of a working mans bench.

@defaultuserid1559 10 ай бұрын

Interesting and memory triggering. Some guys at college had these receivers and they could sound really good with the right speakers. I remember reading a review saying these receivers were basically an Astro-Sonic console stereo transplanted into a receiver format so Magnavox could get a piece of the action selling component stereo systems. I've seen these at Goodwill for $10.

@justsumguy2u 10 ай бұрын

I love watching receiver/amp troubleshooting, and this one is very interesting. As an aside, I had no idea that Magnavox made stereo receivers

@totallysmooth1203 10 ай бұрын

I doubt they did. I would think they just re-badged cheap Japanese imports.

@alanmaier 10 ай бұрын

@@totallysmooth1203 They did design and build them in their Tennessee factory. This was the entry model out of 6 models of true receiver. The top model was groundbreaking as it had a digital display instead of a dial for frequency. These evolved into the Philips brand later on, which are sought after

@zx8401ztv 10 ай бұрын

I did wonder if the output transistors were matched pairs or matched pears for fruit lovers :-D Sorry silly mind :o)

@johnalbanese30 10 ай бұрын

It would be great to be able to see what you are doing. Eather we see your hands, or the camera is too far away

@scrappy7571 10 ай бұрын

Not many of those units around. Cool that you could get the amp working with only a few parts. Are those new outputs a good substitute?

@JordanPier 10 ай бұрын

Yes.they seem to be electrically identical.

@larryshaver3568 10 ай бұрын

true my Dynaco sca-80 was made in 1970 and it had all silicon transistors

@robertheer2708 10 ай бұрын

Could you please tell me how to test a stk461?

@JordanPier 10 ай бұрын

Youll need either the datasheet or the schematic diagram for the machine its installed in. This will tell you how its wired, voltage points, and characteristics so you can test.

@alanmaier 10 ай бұрын

I am curious what the actual power output is from that model. The 300 was the entry model from the true component series of receivers.

@v12alpine 10 ай бұрын

Based on the single ended rail voltage I'd guess about 20 WPC

@jdpinbaytown 10 ай бұрын

It's 10 WPC according to the Shop Manual, It's actually my Receiver

@scrappy7571 10 ай бұрын

COOL! How did you acquire this? Not many around. I looked for a service manual/schematic to follow along with the repairs. Could not find any info. @@jdpinbaytown