ฝัง
- เผยแพร่เมื่อ 5 ก.ย. 2024
- In this part, I show how to test transistors o the circuit board.
I also replace the capacitors and check out the preamp and tone control board.
Finally, I replace the old TA-100WA Power packs with the new replacement modules from Pyramid Audio. This is not a paid add for Pyramid Audio. I purchased them through their eBay store after reading about them. Hopefully, they will prove to be a good substitute/upgrade for the old TA-100WA modules.
Tony, I really appreciate the detail that you put into your repair videos. And also, the practical tidbits that you include, which I may have forgotten about, after loving electronics for over 50 years!
I’m so thankful I found your video. There isn’t much info online. I completely disassembled the amp. The front panel was really annoying me, so it had to go. The one I’m repairng has the same problem. Left channel not working. I’m almost 100% sure the issue in in the switches. There was a large historical layer of dust and debris all inside the amp. Amazingly it still had its wooden cover in good condition. Unfortunately, someone else was in the 9100. On the left side they used some kind of weird pink glue instead of thermal grease to transfer heat from the TA-100WA to the heat sink.
The easiest way to remove any of the boards is to heat the solder up and push the pins through the board instead of messing up the nice winds around the pins. The previous “tech” had much worse connections than you displayed. Thanks for the video, sir.
I Remember this KA 9100 Bought it at the PX and it provided me and the rest of 2nd Ops Bn, with many hours of Rest and Relaxation running at full power into a pair of Bose 501 and a set of Rectalinear Spks. Derek and the Dominos "Key to the Highway"
Led Zep " When the Levee Breaks" , Stones " Brown Sugar" And many more.
I am enjoying this series. At this rate, it should only take 17 episodes.
How ever many it takes.... ;)
Tony, you always add value by showing the "little things" like testings tr's in circuit. Love that!
I did pickup a KA-9100 for a Recap/Service years ago. The front chassis was a nest which I had put back together and sold it. KA-8100 is easy and Pioneer SX-1050, 1250 and Sansui are model examples of design thoughtfulness.
Great job Tony. Looking forward to the next episode. Thanks for sharing.
Good work, Tony! Definitely not a very serviceable construction, I admire your patience!
Thank you for digging further into this one. It keeps delivering more surprises.
0:00 Intro
1:10 First look at the Pyramid Audio TA-100WA replacement modules
7:25 Testing the power amplifier driver boards
14:04 Testing the other channel
14:47 A closer look at the driver boards - Previous work has been done!
18:48 How to test transistors on the board using a DMM
25:21 Xcelite 175M wire cutters demo
27:01 First test (at half voltage) of rebuilt driver board with power module installed
29:03 How to set DC balance on amp module - Multimeter vs Analog Null Meter
33:05 Servicing the preamp and tone control boards - a lot of disassembly!!
35:18 Left channel is assembled - final comments
great restoration work, enjoyed watching the whole process. Thank you , very interesting. I enjoy watching as a hobby, wish I had your knowledge. I'm trying to repair an amp but I have no clue. I still give it a go!
I end up disassembling 90% of the units i restore Just because its easier to thoroughly clean the chassis
Thank you Tony, another good video.
Gran trabajo!
excellent video. Nice work! These were quite the amp when they were first released.
Nice work Tony. I have three pair of Xuron flush cutters that have the lead keeper on them. I love them. Keep the small lead from flying off and potentially causing a short down the road. Just as a small note for the 2SC1400 you mention. It is well known to be a component that has a high failure rate so I remove them anytime I see them. In fact I found one about a week ago that was causing reduced audio in a Kenwood integrated. As you mention the KSC1845 is a great sub, but I’d you want to maintain the high gain if the 1400 I like to use the ZTX694B. I was smart enough to buy a couple dozen each of the STD03N and STD03P before they went bye bye. I need to get a good look at the front and back of their board so I can etch my own for future replacement of these Kenwood chips.
Thank you so much for the great information! I'll have to add the 2SC1400 to my list of problem transistors. Thanks also for the suggestion of the ZTX694B. I might even have a few of those in stock. Thanks again!
Danke fürs zeigen. Weiterhin viel Erfolg.
Awesome work so far as per usual, Tony!
Can’t wait for the music Tony….!!
1. I believe some of the controls on these amps were sealed and had to be punctured (typically with a hot needle) in order to lubicate them. If that wasn't the case here, you're lucky!
2. Not sure changing the diodes matters as long as the forward voltage is comparable and rating is sufficient.
I would actually prefer the pair of cutters that hold the wire when you cut it. The last thing anyone working on this equipment needs is to have a piece of wire fly off and land somewhere on the PCB and short something out
Pallidan also makes a pair that holds the lead.
Merci for this video. And thé explanation for check transistor.
One thing about Japanese small signal transistors, the pinout is almost always "E-C-B"
If you can’t remember which is higher on testing transistor.. collector has letter L to remind you it’s lower than emitter .
It's also part of the reason why a transistor can't be replaced by two diodes, they are both different and tightly coupled to the base.
@@Enigma758Diode voltage drop varies by type, so you could match two coupled diodes that display these exact results. No conjecture to form here, I'm afraid.
@@paulb4661 True, you could match two diodes to get the same readings, but the real reason has to do with the monolithic construction of a transistor.
@@Enigma758 Precisely, has nothing to do with the voltage readings disparity between a BJT and a couple of diodes joined at the Node or cathode, since these can be easily made to match. So it's none of the reasons for non-equivalence, not one of them.
Another one I just made up is that the emitter has an arrow, something 'more' than the collector.
Wow. good work. Mike.
I must admit, if and when I see an amplifier (or anything else) with a proprietary IC, it's a big turn off for me.
Must be some kind of jig they use when assembling these units.
How much do those drop in modules cost compared to IRS2092 boards? MOSFETs are far more available nowadays compared to those oddball power Darlingtons.
2092 & mosfets are a whole different ballgame..directly , it won't work here..
What kind of oscilloscope would you recommend for someone to get started with FM tuner alignment? Does it need to cover the FM frequency itself, or would a 50MHz or 100MHz be sufficient (audio and possibly IF)? Would Siglent SDS1052DL+ be any good?
Different people will have different opinions about this. In my opinion, a good 60 MHz analog scope will work fine, if you are just interested in doing AM/FM alignment. I like the old Tektronix and HP scopes. Leader & Sencore both have older models that you can usually get for a good price and they usually work without having to do much to them. Newer digital scopes like the Keysite, Rigol, Siglent and Instek to name a few are pretty good as well, but they may have a bit more of a learning curve, if you have never used a scope before. That said, the newer digital scopes have a lot of features the older ones don't, but at the cost of the steeper learning curve.
@@xraytonyb Thanks for the detailed info Tony! I have not touched a scope since I was in trade school, but I'm sure I will figure it out 🙂The tuners themselves are the hard part, but I've learned a ton from watching your videos already...
I found a data sheet that covers the whole range with pinouts and example circuits for each. Unfortunately, every time I tried to share a way to get to it, my post would disappear.
You Tube is really picky about posting links.
@xraytonyb yeah, I know. These weren't even links, but just suggestions (long spelled - words for punctuation and extra spaced out) with how to search / find them. I'll go back and see if I can find them in my history. I'm sure it would help in the future.
And it did it again.
Just look for ta-100wa pictures and you'll find it
I have it on my phone, along with the STK's, if need be.
Hey Tony u got a email to contact you to get a opinion on problem i have with my perreaux r200i amplifier?
This is why Kenwoods are cheap. They are not easy to work on.
Annnnnd , another good one! Enjoyed watching and learning. Thanks!