Marantz 1300DC - Part 2

[@alanvandusen76]

I think the solder and chat would be great. Thanks for all the great videos and for spending time with us.

[@marcodoria]

Solder and chat! Solder and chat! Vote for solder and chat! Just kidding, the thing I love the most is to hear your honest and passionate talk about the things we all really enjoy! Nevermind the mistakes, he who has not made any, in my opinion hasn't done anything. If he has, than I will take the first stone. As always, thank you Tony! Cheers from the Azores, Portugal!

[@TrevorsBench]

Thanks again Tony, I always vote for solder & chat

[@jeffberwick]

Always nice to see you diagnose your own errors. That is real life! It helps followers so much more than a "flawless" replacement of devices.

[@davidbailey6350]

Tony, go for the whole Kit and Caboodle…. I enjoy the whole process. Thank You….

[@aarondavis8398]

saulder and chat are the best 👌 great video 📹 👏 keep up the fantastic work

[@mikepxg6406]

Solder....

[@HazeAnderson]

... and chat.

[@26Jorgeb]

What a big puzzle you have solved!Amazing.

[@mackfisher4487]

Capacitor lug connection, brilliant idea Tony to make up two ring terminals soldered together to connect amp's caps together 20:09.

[@TrevorsBench]

I did the same thing just yesterday on a Sansui G-2000 i'm servicing. I installed one of the driver transistors backwards and was confused why I only had half a sine wave at the output. The silkscreening font is tiny and with my bad eyes I thought a E was a B. No harm done, once I discovered my error and fixed it the amp ran like a champ, no damage done

[@jdmccorful]

I'm good with solder and chat, you never know what you can learn. The patience and time are the mark of the good tech. Thanks for the look and your sage experiences.

[@zx8401ztv]

Tony, We all make mistakes but we don't film the evidence Ha ha :-D The original transistors were odd.

[@tamtgirl]

as always, i'd rather have a solder and chat kind of video :)

[@kenelsbernd276]

👍

[@kylesmithiii6150]

Thanks for the video, that was very good! I understand that the owner of this equipment wants to maintain its originality as much as possible, and I am like that too. However, I would make some changes in the power supply circuit, without cutting traces or breaking anything, I would include a positive and a negative voltage regulator such as the LM338/LM337 pair and neatly install jumper wires in the PS circuit. As we know, these regulators are quite stable and provide both thermal and over-current protection. We remember, for example, how bad the original PS of the Pioneer SX-1980 was, to the point that you installed a brand new PS board. For this Marantz 1300DC, I understand that it's PS has demonstrated to be very vulnerable, it burned pretty badly and the root of its regulation relies on a single Zener diode.

[@diabolicalartificer]

Re thermistors, I know a lot of folk don't like em but you mention a thermistor still has some resistance when warm, say 1 ohm, that means a 120v mains supply can still supply 120A (potentially). The winding in a transformer primary might be 4 - 10 ohms or more, a fuse has resistance too, a 5A fuse I just measured has nearly 1 ohm resistance, the transformer isn't 100% efficient either,losses everywhere. Re heat, use a bigger thermistor like SG-420's possibly. Grand video as always, thanks.

[@adalbertus777]

Solder and chat, that's what tiggers like the best ;) BTW - beautiful camera shots, Tony. A pleasure to watch.

[@t1d100]

Good stuff

[@흑석김용호]

From my experience, this is Korea and I write with Google Translate. If there is a lot of fuse resistance but the fuse resistance is not completely broken, 33Ω 4.7Ω etc . Memory not correct Bias goes up and eventually burns out the transistor due to thermal runaway. The q710 2SA970 aged due to overheating for a long time, so the hfe value dropped and the bias value could not be adjusted.

[@craigm.9070]

I'm in for a solder/chat on that board rebuild! The old "measure twice, cut once" monster reared its head on those pinouts. All is well now though, thanks for your time Tony!

[@HazeAnderson]

ditto :)

[@greengrayradio1394]

Nice analysis and corrections, Tony! Strange they didn't fit a "soft start" arrangement originally with that big inrush current. And also, the thoughts about switching off and then on again right away, with the high inrush current then in some circuit designs. Most TO220 transistors are "B-C-E" , also the bigger TIP packages. The TO126's are all "E-C-B" as I have found. I wondered as I watched if you reversed the "TT" transistors with metal side up, but in this case it didn't matter.. Replacing the older MJE2955 and 3055s (E-C-B leadout) today is not easy, the newer ones are reversed

[@aminbjt5843]

Hello Please explain how to work with the distortion meter in a video Thankful LDM171

[@johnnytoobad7785]

I'm always curious about the "thought process" you go through to find proper substitute transistors. I ran around in "mental" circles (way back when) in attempt to find modern "substitutes" for first gen. SONY FETS. It ended up being easier to re-design re-build the board using low noise bi-polars.

[@roroseppel2077]

Tony is getting older !!!

[@kelleyhagan960]

Who isn't !

[@ampdoc]

Solder and chat please!

[@meraydin1]

Regarding relay contacts; I remember the ark is generated (most) during the contacts seperate under high load (because electrons cannot stop instantly :)). During closing it should not hurt that much. Or this very old knowledge (of mine) is wrong?

[@discow00t]

Well, forget about this error. You solved it. What's funny is, that none of your viewers (including myself) spotted the mistake when you put them in on your previous video 🙂

[@Forensic1Man]

Hi! Does anyone know where I can get the schematics to a Model W158 Ultrasonic cleaner that uses three 6GT5 tubes? I can not find the schematics easily on the web. Any help would be great!

[@johnwagner800]

xraytonyb, Solder & Chat- sign me up. Please don’t be so hard on yourself! I’m sure your customer is very happy to have an honest tech working on his equipment. I get the confidence I need to take on some of this stuff from you. It’s because of you that I’ll go back and revisit some of those projects I put down a few years ago, and take another look and hopefully, finally, resolve what I couldn’t see before. Remember, you don’t have an ex-parrot, your parrot has not shuffled off his mortal coil…Sincerely, John Wagner

[@jimomertz]

A big Homer *Doh* 🤦🏼‍♂️ to you. 😂. I’m a meat and potatoes guy. I’d vote for going straight to the preamp, and skip the chat. 🙂

[@petergoose8164]

Just a question. Which of your videos talked about connecting an oscilloscope to mains?

[@wolkewietje01]

Skip the solder-chat and elaborate more on the front end please

[@HazeAnderson]

Hey those idiot boots will keep your feets dry!! 😆

[@sonnylou8087]

😴🙈

[@swamtoherbutt]

Solder & chat 👍🏻

[@xray111xxx]

Any parts to get is hard. I ordered some caps on Mouser. It was crazy.

[@chendolphin572]

Hi xraytonyb, I have been following you. You do a great work. I work for NextPCB. We would like to sponsor your projects. You can send a DM for more details. /Dolphin

[@tntring]

I like Tony just the way he is... unsponsored. I was just watching a video where he called out a "prospective(?) sponsor" for jacking up prices after he released a video... Kudos Tony!~!!! Keep up these AWESOME Videos!! (Oh, and I have been itching to check the price of those 10b's now!!! LMAO!)