• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Recap list & Advice for Pioneer SX1000TD

H

History Dude

New Member
Hey gang I am in the process of my first recap/restore of a unit and I am attempting to resurrect a Pioneer SX 1000TD. According to the serial # it dates back to Spring 68 so I am excited to get this puppy rolling again.

The receiver seems to work fine but the right channel is out. I plan to do a complete restore ..

My first request is a recap list if anybody has one for it. I am also all ears on any other free advice that I can use over the next several weeks as I take my time restoring her..

I apologise in advance for my other stupid questions going forward.
 
Register to hide this ad
Hello. I was given a Pioneer SX1000TD in nice visual condition. I think it has a dead short and was wondering how to go about figuring that out. I have limited knowledge of electronics but lots of free time to learn (retired) I have a digital multimeter, know how to solder, familiar with deoxit and can identify resistors, transistors, capacitors, foods etc. When I plug the unit in and turn it on the lights go on and in a split second the main and only fuse blows. I'm thinking maybe a bad resistor or a power output transistor but I don't want to guess. I want to know and understand how and why I know. If I need to buy equipment I'm ok with that. Oscilloscope? DBT? Thanks. No rush.
 
Foods should be diodes. And I know this is a long learning process. If you know if Books and videos of the subject that would be great too but hands on is best for me. As I said. I got the receiver for zero money. It's a good practice piece and although I'd prefer to save it I'm not totally against making things worst and bringing it to a pro to repair afterwards
 
Something in there is drawing too much current - DBT would really come in handy.

Then you can diagnose. Sure sounds like a shorted OPT though. Good luck!
 
Thank you both. Ill get to working on it. I saw a YouTube piece on how to check OPTs with a MM. Ill review, build a DBT and give it a try.
 
So after reading an incredibly informative easy to understand article titled, bipolar junction transistor testing basics, written in 2005 by Echowars. (Some of you guys are Gods) I've come to the conclusion that I need to replace 1 of 4 TO-3 transistors on the SX1000TD. I have two-ish questions. (Reminder extremely new at this.)
1, when I read threads about re-capping receivers no one ever says to replace the bad capacitor only. Its always "replace all". Do the same rules apply for output transistors? I mean why shouldn't I just replace all 4 since I'm already in there replacing 1? What benefits/problems would that cause? 2, All 4 OPTs are Toshiba 2sc793. But, from the left (if sitting behind the receiver) the 1st and 3rd OPT has a red Y under the number. The 2nd and 4th have a red BL under the number and a fat red dot above. Are Ys and BLs diferent? Most of the transistors I see on eBay are Y. And not that I don't trust all the good sellers on eBay but I'd prefer to put new parts in this unit. Are there any readily available replacements for the 2sc793?
 
NTE shows it as their NTE130 which is a 2N3055. The letter should refer to different hfe ranges for it. If it were me I’d replace them all so they are all the same. I’d be weary of eBay.
 
Thank you Mr Rules. Yes. I plan on replacing all 4 and in will go with new and not eBay. Also. In response to your earlier comment about hifi engine. I have the original book that came with this receiver. It has operating instructions, a large detailed parts list and drawings of the innards. It would be super helpfull if I knew what I was looking at and what they all did. I'm working on that! My understanding of electronics has quadrupled in the past few weeks. But that ain't much when starting at zero. Thanks again! Still got to build my DBT before i begin surgery.
 
Ok. This may not be the correct thread but its still mainly about my SX1000TD. I'm getting supplies together to build a DBT per above recommendations. Got a few questions. I've read a few articles about building it. One from here and and one from Radio Museum (RM). The RM article says that I should use a bulb 1.5 times higher in watts then the receiver. I think the SX1000TD is 130 watts (I'm not home at this moment). The likelihood of finding an incandescent bulb like that is slim. Since most of these posts are pre-incandescent prohibition. But what really confused me is the author, Paul Pinyot I believe, said if I can't find a bulb that large then hook up a multi socket power strip and add bulbs. What??!! If a power strip works then why do I need to build a DBT? Why can't I just line the strip with plug in bulb sockets and bulbs and leave the last socket open to plug the receiver in?
 
MFF said:
Ok. This may not be the correct thread but its still mainly about my SX1000TD. I'm getting supplies together to build a DBT per above recommendations. Got a few questions. I've read a few articles about building it. One from here and and one from Radio Museum (RM). The RM article says that I should use a bulb 1.5 times higher in watts then the receiver. I think the SX1000TD is 130 watts (I'm not home at this moment). The likelihood of finding an incandescent bulb like that is slim. Since most of these posts are pre-incandescent prohibition. But what really confused me is the author, Paul Pinyot I believe, said if I can't find a bulb that large then hook up a multi socket power strip and add bulbs. What??!! If a power strip works then why do I need to build a DBT? Why can't I just line the strip with plug in bulb sockets and bulbs and leave the last socket open to plug the receiver in?
Click to expand...
Plugging the amp into the power strip will not limit the current, as it will be parallel to the bulbs.
The bulbs in the DBT must be in series with the amp. Adding more bulbs in parallel with each other increases the power that gets to the amp. If you don't understand that explanation study series and parallel resistor circuits, and Ohm's Law.
BTW, A 60 watt incandescent bulb should be fine for a starting bulb with a solid state amp.
 
Thank you sir. I do understand your answer. I am studying many areas of electronics. Asking questions on this site and getting answers from extremely experienced and knowledgeable people such as yourself is part of my studies. Thank you!
 
NTE devices have a reputation for questionable performance and discrepancies in their specs. You might want to give a look at the MJ21194G as a viable replacement for your outputs. They are made by On Semi (very reliable market leader) and are available at Mouser:

https://www.mouser.com/ProductDetail/ON-Semiconductor/MJ21194G?qs=HVbQlW5zcXVQxZkOqmVvOA==

It might be a good idea to post a thread in the Pioneer forum to get the thoughts of the experts there as to the suitability of this transistor, as my knowledge level is only moderate.
 
Last edited:
Thank you for that! I'd hate to go through all this only to find I installed a bad part. Btw. I thought I WAS on a thread in the Pioneer forum. I'm not sure which is more difficult. Learning electronics are learning to navigate forums and threads. But I'm having fun doing both and that's what counts!
 
I believe this is the Solid State Forum...look at the top of the page (under the banner advertisement).

One other suggestion...it's best to start your own threads, rather than try to piggyback on someone else's. That can cause confusion when the OP has one set of questions and the "piggy-backer" has different questions, even though they are both on the same topic.

Welcome to AK.
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom