The Marantz 2275 - It came back - This time with a blown fuse - Plus FM tuning meter repair
Ғылым және технология
The nice Marantz that I relamped with LEDS came back with a blown fuse. Turns out one channel was blown. I went ahead and replaced the output transistors on both channels. I re-centered the FM tuning meter too.
If you would like to support my video efforts please consider making a donation at www.paypal.me/NORCAL715 Remember with your help we can keep these things out of the landfill, out of the recycle bin, and out of the E-waste facility! Thanks for watching.
Thank you to these people that have supported my channel by making a donation or by having me repair their unit.
Sherri Parsons Jim McCarthy David Arballo Steve Navarro Keith Claro Frank Conlon Graham Foral Bob Hendrix Jim Meschler David Jacobson Randy Fink Scott Kullen Obaid Khan Robert Brothers Timothy Edds Brian Gay Owen Flint Dana Dainels Tyler Bridge Dena Hamilton Paul Agbuya Samuel & Nancy Guich Dot Morgan Timothy Ritchel William Holloman Cynthia Adams Andrew Oros George Savage Graham Foral Paul Agbuya Philip Brown (Thank you for monthly support) Scott DuVall Christian Brenzel Russell Houtz Philip Brown Michael King Erick Pastor Robert Ettinger Christopher Cicero Heath Lasswell Timothy Ritchel Benjamin Rubio Michael Dukes Dot Morgan Casey Cane Teri DeLeo Kelly Knutson Howard Goble Diana Williams Reed Graham Christopher Wang David Ammerlaan John Johnson Shaheed Amirkhan Brett Sherry Joseph L Ozvold Sweidan Omar John Eggers Linda Kuo Daniel Pyles Melanie Branton Lisa Sklar Barry Marchant John Harper Larry Mcdonald Annette Lewis Howard Goble Hugo Tajimaroa M R Rajesh Dan Latorre Uri Cohen
Follow me on social media
Facebook
Instagram
Twitter
@NORCAL715
email me NORCAL715videos@gmail.com #Norcal715Videos@gmail.com
00:00 Intro and current tests
01:12 Power supply schematic
02:13 Power amplifier schematic
02:51 Ohm meter tests
04:57 Output transistor tests
05:40 Driver component tests
09:58 Replacement output transistors
13:11 After repair ohm tests
13:32 Audio adjustments
15:27 Left channel transistor replacement
17:37 Audio power tests
19:00 Thermal image results
20:50 FM tuning meter repair
24:33 Final thoughts
25:40 Closing words
26:37 Bonus footage
Пікірлер: 62
Saul Marantz would be pleased to know that his equipment is so loved and so revered this many years later.
Great video, now I can fix my Marantz 2275 with similar problems. Thanks a million
Nicely done! Thanks for the video.
Just when you thought it was safe to watch a Norcal715 video without acetone..... Jokes aside, definitely one of the more interesting repair videos of late, great repair!
Great attention to detail.
Great tuition. You have clear video and I enjoy seeing you troubleshoot in detail. Thanks and keep them coming.
@groovejet33
2 жыл бұрын
hes deffo a one off. his troubleshooting skills and teachings are best ive seen. like when testing a pcb, ground connectios and tracing faults, i learnt loads from him. then he dissapeared for couple years. now hes back.
@andrewhenderson9474
2 жыл бұрын
@@groovejet33 Best I have seen on KZread. Including Mr Carlson
Hi Steve, good catch, great fix and the unit was worth it.
Nice work on tedious meter work. 🙌 REALLY liked seeing the vintage Sencore SG165 being used on vintage equipment. ABSOLUTELY blew me away when you pulled out the acetone. 🤣 Great stuff Steve.
amazing video.excellent analysis.thenks
Hi, I hope everything's going well, I suggest you can teach us how select replacement transistors when we repair vintage Amps like this Marantz. That's my request. Regards.
I really like the way you do your videos. Not so basic that its boring. Thank you.
Another excellent video and another satisfied customer.
Good job thank you..
You do work fast! They really don't make stuff like this anymore.
That is what you get for not cleaning the faceplate in the last repair. Good repair
Great job =D
I'm happy with that
👍...great memories..!!
Would check those emitter resistors as they likely have drifted in value up with having the massive current pulse from the failed transistors put through them. With the failed ones a decap with a microscope view would be interesting, and then some comparisons with the still somewhat working ones. Going to guess the PNP failed first, silicon PNP power was always a harder transistor to get right, unlike Germanium, which was the opposite.
@norcal715
2 жыл бұрын
I did check them, just didn't record it.
Hi, Great vid. That thermal imaging camera is awesome! Where do I find one? Thanks, Rob
@norcal715
2 жыл бұрын
It is the Flir one pro.
I'm sure my old Marantz needs some TLC service as well (not being used at this moment). Also my Adcom 80's GFA-555 amp. I still run the Adcom hard and it is stock. I'm sure it needs to get tuned up. Probably should get it tuned up before something shorts and fries my Darlington outputs. Aww I forgot I also have a 70's Pioneer receiver/Tuner rated at 45 Watts per channel which easily runs 100Wpc clean that should be tuned up.(also not used at this point). Guess I need to save up and have you go through and make them right again. Thanks for the vids. New equipment is garbage!
was surprised they were silicon and not germanium...
I had a sansui reciever with transistors like that and one channel was bad causing damage to the driver circuit. The other channel was okay but if you put the fuse in the dead channel it would blow right away. I took it somewhere and they tried to repair it but was unsuccessful.
@norcal715
Жыл бұрын
Too bad, they were great units.
Great video. I'm glad you are showing how to refresh these classic receivers. They still perform on a par with the best amps today. I noticed you upgraded the outputs to the higher rated mj21195 / 96 pair, perfectly fine subs at even higher ratings .Overkill, in fact. There are many counterfeit power transistor sellers in China, so buyer beware. Buy these parts from a trusted US distributor or you may be sorry. Also, It looked like the mica pads were put on dry originally (not sure, maybe just clear grease?), glad you put some fresh silicone grease there. In your earlier video, you changed the indicator bulbs to LEDs. Did you use white LEDs for the pin bulbs, and cool blue for the fuse bulbs. I plan to do this on my 2275 and will buy individual LEDS, so I wondered what exact color for the pin LEDs, warm white or cool?
@norcal715
3 ай бұрын
The customer supplied the LED kit so I do not know where he purchased it from.
Nice work. I think you could have centered that tuning meter without disassembling anything by following step 11:8 in the FM alignment section of the service manual. Center tuning adjustment is made by adjusting the upper core of the discriminator transformer L201 to center the needle. At any rate, job well done.
@norcal715
Жыл бұрын
That step only works if the tuning meter is mechanically centered. I tried to adjust the discriminator and when the tuning meter was centered the alignment was off. Plus with power off it needed to be centered (OCDness)
Great Work! I got a Marantz 2252 works perfectly except the FM radio, it drops out once in a while and around 10-15 seconds after it comes back, it stays normal after it warms up, jut wonder what is the problem with the FM? Any idea?
Hi. Thanks for the great class. Congratulations on the high resolution video. What I would like to ask is about my 2275, it has 2SD733/2SB697 transistor pairs on the outputs, they are working fine, but are they correct for this Marantz model? I also have 2 pairs of transistors 2SA747A and 2SC1116A, will they be suitable for model 2275? Thanks.
Did you check the bias adj pot ?
hello , can you make a video on how you organize your lab ? i am having hard time to organize mine , how the equipment that you use often thank you sir can you tell please at what charts do you use for esr test , how do you know by hart what the value should be for every cap an , thank you
Tunung :D
Am I seeing things or was there no heatsink compound on the original transistors?
@norcal715
2 жыл бұрын
It had just silicone dielectric grease only.
@SeanBZA
2 жыл бұрын
@@norcal715 Probably had all evaporated away, leaving the output devices with little heatsinking and then one transistor failed.
maybe over load on the output speaker so give up the transistor driver.
I have an Onkyo tx-sr505 with recently blown output transistors on SBR. I haven’t used surround back speakers in over 10 years. Is it safe to remove the transistors and continue using the receiver without the back speakers ?
@norcal715
2 жыл бұрын
Should be ok, You may have to remove the driver transistors if one of those are bad. They can cause a DC offset on the speaker line also
@jeisonsanchez4842
2 жыл бұрын
@@norcal715 Perfect. Thank you so much for your reply and your excellent repair videos.
The owner could have a defective speakers, without even knowing it.
hi Norcal, hope your well m8? In UK , The goverment have reopened everything, but i know loads of Peeps getting covid, doesnt make sense. stay safe my mate
How much did you charge the customer for a job like this? Just the labour without parts? I never know what to ask, what is the right way to calculate the price. Thank you.
@FixthisCD
2 жыл бұрын
I would charge parts and labor. Had nothing to do with original issue
@norcal715
2 жыл бұрын
On the comeback I charged one hour for the amp repair plus parts, and one hour for the meter repair. The total with parts was $150, but I do this in my spare time and charge less just to do it. The normal labor today would be between $75 and $100 per hour, it took approximately 3 hours total. As stated in the video I cut the customer a break.
i was given a RS Analogue multimeter, and i struggle to use it, any simple tips? It was never used and came from a large chemical works in UK called ICI (Imperial chemical industries) like alot of stuff, its been bought out and is no more, so i got a multimeter
@norcal715
2 жыл бұрын
Send me a clear picture of it to Norcal715videos@gmail.com and I will try to help you.
@groovejet33
2 жыл бұрын
@@norcal715 lovely
Could you have just replaced the Right channel power transistors but not the working Left Channel (Would that cause any problem)
@norcal715
2 жыл бұрын
No issues if you do just one, I think doing both channels will prevent future issues.
What's the cost of repair?
@norcal715
2 жыл бұрын
On the comeback I charged one hour for the amp repair plus parts, and one hour for the meter repair. The total with parts was $150
3amps, 12v, what is the colleration? using ohms law, what does this tell you? what were you expecting?
@norcal715
2 жыл бұрын
A dead short!