How To Service A Vintage Pioneer SX-434! - Lot's Of Jumpers! [Do It Yourself!]

[@randyknowles2324]

I'm just about ready to service my SX-434 unit, and the video was of great help. Thank you for taking the time to post this. You did an excellent job of showing and explaining the repair.

[@TinkeringWithT]

Awesome! I’m glad I could help! I hope the service goes smoothly. Thanks for watching!

[@martyjewell5683]

Great video of a swell stereo receiver. My first component receiver purchase in 1975 (after military service and broke) was this SX-434. Traded it away but found a junked model a few years back and had it serviced for $60 and use it in my 900+ cu/ft kitchen hifi system. These "budget" receivers were boss, all the basic features necessary for good sound. It's amazing how much quality was built into these receivers from several manufacturers. Most of them had no problem driving 4 ohm loads.

[@TinkeringWithT]

Thank you!! I agree, they are incredible receivers!! I really love the warm tone they give off. I’m glad you got another one and put it to use!! It’s a shame they don’t produce receivers with the same quality these days. Thanks for watching, and thanks for your service!

[@martyjewell5683]

@@TinkeringWithT- kind words sir. Funny how I didn't appreciate the little SX-434 until Covid hit and my wife started working from home. We had to put her "computer stuff" on the dining room table for her office. I couldn't play the "big stereo" with living and dining room speakers so I got to dig the kitchen system. My SX-434 drives a Nakamichi BX-1 cassette deck and two pairs of speakers; Synergistics S12B (6w min) and Boston Acoustics A-40 (5w min). The A-40's really shine being driven by the SX-434 and can get plenty loud and stay clean. Hifi makers cared about their customers by offering extensive lines with products at many price points. Also, with budget components you can Trade Up to more advanced stuff as I did.

[@mikefriedman6394]

This is a great video. I have an SX-737 on my bench right now and I have learned tons of tricks from all you guys

[@TinkeringWithT]

Thanks for watching!!!

[@hereforthechips7710]

I just purchased a non functioning 424. Hoping somewhat similar. Thanks for making this.

[@TinkeringWithT]

Congrats!! That’s a great receiver. Any luck getting it going?

[@andrewclough660]

Much appreciated T, I was just given one in mint condition bar the tuner pointer lamp that is out. Wish you had of replaced yours but no biggie, I put red texta on it which helps a bit.

[@TinkeringWithT]

Congrats!! They are awesome receivers. Yes, sorry about the lack of dial lamp replacing.. I wasn’t so sure on how to do it at the time! I’ll see if I can do a quick video on replacing it! Thanks for watching!!

[@graemeguthrie2054]

Many thanks for such a detailed video, I enjoyed watching all the tests. I have the wiring assembly experience to do repairs but not so much of the audio testing so good to learn.

[@TinkeringWithT]

Thank you for the kind words! I'm glad you liked it! Audio is a lot of fun, you'll love it! Thanks for watching!

[@munciejournal167]

Very informative video.

[@TinkeringWithT]

Thank you for the kind words! Thanks for watching!

[@briannewell6064]

Yes, there is a bulb in the dial indicator hiding under the metal clip.

[@TinkeringWithT]

I knew it! Thanks for confirming and thanks for watching!!

[@menudo666]

What type of bulb is that?

[@adriansotes3028]

excellent video, I have the same model and the left channel sounds distorted, when I measure the idle current between tp1 and post 27 the reading is 0 mv, and the jumper is cut, what else can I do? , thank you

[@TinkeringWithT]

Thank you for the kind words! Hmm which jumper do you have cut? If I remember correctly you cut jumper A for to increase the idle current for the left channel

[@adriansotes3028]

@@TinkeringWithT jumper A is cut and even so the measurement is 0mV, I think that raising the value of r71 or r69 may increase the idle current ,what so you think about?

[@TinkeringWithT]

Gotcha! Let me take a look at the schematic and I’ll get back to you. Any luck so far?

[@adriansotes3028]

@@TinkeringWithT thanks, I wait for your answer please

[@TinkeringWithT]

Sorry! been busy with work. Do you get any sound out of the left channel? if so it'll probably sound terrible due to the low idle current. I'm wondering if there is an open resistor, or a transistor not functioning correctly on the left channel somewhere. Can you visually inspect the board to see if anything looks abnormal? I'll dig a little deeper into the schematic in a day or so when I have a little more time! If everything checks out we may have to make sure we have all the correct voltages coming from the power supply board.