TASCAM Portastudio 424 Mk2 Totally Dead

This one was shipped in no power whatsoever

[@PETECAROLAN]

Enlightning video. Nice to see the fuse workaround. I have a Yamaha MT3X. Very similar to this one. Still works nicely.

[@mfbfreak]

Same! The Yamaha has the benefit of having an external power brick that you can just swap out with any new 12v 1a supply. But they don't have the cool VFD. The VFD is what requires the "exotic" 3v and 40v voltages.

[@PETECAROLAN]

@@mfbfreak Remixing a song on my Yamaha MT3X 4-track Cassette Recorder, Just for FUN www.google.com/imgres?imgurl&imgrefurl&h=0&w=0&tbnid=AAAAAAAAAAABAM&q=yamaha+mt3x&usg=AI4_-kRjJsVx0L5spu9Px-77rDKUFrSPKQ&vet=1&docid=AAAAAAAAAAABAM&client=ms-android-samsung-ss&kgs=5ca934760cf5104a&shndl=-1&shem=mslc&source=sh/x/srp/img/m1/2

[@PETECAROLAN]

This is the one with an internal PSB.

[@mfbfreak]

With regards to using the other 120v winding - if you try this at home, make sure that the 120v windings aren't supposed to be run in parallel. The tascam's system is common, but so are systems with a voltage selector that chooses between running 2 120v windings in series, with the selector connecting those in parallel for 120v use. This saves the manufacturer on coil winding wire thickness.

[@peterlarkin762]

Good point, most modern transformers use both 120v windings in parallel to achieve the specified current rating. If only one is connected, the transformer's going to overheat with a normal load.

[@12voltvids]

​@@peterlarkin762no they don't. Only dual voltage run a center 2 primary windings. You wire them in series for 140 or parallel for 120. Three are 120 and 240 volt wound transformers. Most domestic products only had a single winding because it was cheaper to make and in many cases would not pass ul certification. The reason they connected the windings in parallel was not so much because it increased the current, it's more for safety. Having an open winding will act just like a secondary and produce high voltage across the terminals which not only provides a shock hazard but the open coil voltage can be much higher and could result in the winding arcing over and causing a short. Incidentally if you have an inverter type microwave oven i dare you to unplug the magnetron and tun it on and see what happens. Good change the inverter transformer will burn up. High voltage builds up and arcs over. This is one of the reasons inverter microwaves will turn off after 3 seconds if they don't detect the magnetron drawing current. That's to protect the inverter. Once the magnetron wears out and falls below the expected load. Disconnect and you have no load. It will shut off but damage may already be done.

[@mikemoyercell]

i love that bird getting shocked and how you narrated it - never gets old! LOL

[@robbieblackmon1801]

Agree. Fried bird never gets old! The narration totally sells it. Also the Tascam brings back memories.. Our group's sole demo was recorded on one of those. Still have the 4-track master somewhere in a box of rubbish. We got rejected by everyone.. even 4AD who, at the time, were scooping up almost anybody. Just not us!

[@3dsmaxrocks699]

Finally a Tascam multi track!

[@12voltvids]

😁

[@tomj4506]

@1970, just out of diapers I got a job at the local shop. I did smalls & what was called N work ( cleaning toilet, building stands, deliveries, etc ). I put in so many transformers! Then I was working on a low end Panasonic stereo & noticed a fuse within the trans. on the schematic ! Live & learn. Funny thing almost nobody noticed them either. LFOD !

[@dalemettee1147]

OK, those clips. I think that these kind'a clips are used for retaining the power cord. They could've been installed at the factory. One was dropped in the unit and another was installed but it too got lost in the unit. Too bad that there wasn't enough time to retrieve them.

[@FrankJCarver]

That was a great repair.

[@thinlizzysupporter]

I have a Yamaha MT3X which is very similar to this in functionality and capability. At high speed with dbx the recording quality is excellent. Once you have recorded on tracks 1 - 3 you can mix them together and record the result on to track 4. You then record over tracks 1 - 3 etc. I used to record all 4 tracks and then record out on to a hi-fi vcr then record that back to the portastudio. I could do that a couple of times without serious loss of quality. The good old days haha !

[@peterlarkin762]

I had a toroidal transformer spontaneously combust in an Audiolab CD player. It wasn't an over-current situation: the thermal cut-out had failed AND shorted out a winding. It was completely burn to a crisp by the time I smelt the magic smoke. The player had a mains power fuse but it was specced to run two transformers and didn't blow. Thermal cutouts are an extra safety feature and it's crazy not to have an adequately rated mains fuse per transformer

[@angryshoebox]

I still have my Tascam Porta 3 that I got back in the '90s; I recorded a ton of stuff on that machine. It's the most basic model of Portastudio, or was, rather. I think the 424 was the next model up. Anyway, I wish the porta 3 had double speed capability, it only ran at the standard 1 7/8 ips cassette speed.

[@MrJDNJ]

Back in the 80s I had the Tascam Porta 05, and if I remember you could record up to 10 tracks by "bouncing" and mixing the tracks over to other channels (recording a new channel at the same time, etc). I just repaired the stop button on an old Fostex MR-8 and it's been fun recording digitally instead of on tape. I seem to get better mixdown results if I play the recorded tracks back into the computer (alpha audio interface, audacity) instead of using the MR-8 mixdown process onto the SD card. And I might even get a better output signal if I can find an audio interface that has the digital in/out, (but that seems to require firewire usb) because the MR-8 has that option for output.

[@12voltvids]

Yes mix 1 and 2 to 3 record new on 4. Mix them back to 1. Of course these become a mono track so you do things like drums and bass.

[@mfbfreak]

15:20 for anyone wanting to buy a solder sucker, don't get the cheap ones. Spend €20 on an Edsyn Soldapullt, the small model. They also have huge ones, don't get one of those, get the smallest. It's a day and night difference with the generic ones. What also works well are the chinese desoldering irons that are just one of these solder suckers inserted into a soldering iron with a hollow tip. They don't last long, but they're cheap so if you only use it incidentally it's fine.

[@12voltvids]

Yes I had an edsyn soldapult at the shop and it was good.

[@bmw540iable]

Like that introduction real funky Dale Jacobs Cobra 1978.

[@12voltvids]

Yup

[@Truckguy1970]

Have you ever worked on the mixer boards like the ones they use in professional recording studios?

[@jeffadams5510]

Those thermal cutouts like you said are a UL or other market thing.....pain in the arse!!!! Funny how older equipment w/o thermal cutouts survived just fine. Best fix is to do exactly what you did here!!!!

[@12voltvids]

In certain things like an iron, space heater, electric oven, Hair dryer ect they are an essential safety device but in a low power transformer they are just planned obsolesce

[@ricfair9919]

Seems like a good machine for back in the day.

[@AstrosElectronicsLab]

Sounds like the tape path could use cleaning.

[@silviogiampaolo3043]

Obrigado pela postagem!!!!!

[@kelvinstokes996]

Change the solder sucker up for a SOLDAPULLT or a good knock-off of it. They have a way larger vacuum chamber and a larger tip - they don't jam up as often!

[@12voltvids]

I used to have one. Went missing at the shop. I think one of the guys I was charged with firing removed it because after he was gone nobody could find it so we ordered another and this is what showed up from the supplier. It left with me when i quit lol. As did the esr meter.

[@kelvinstokes996]

I've got one of the cheap Aliexpress knock-offs. Honestly, works great!@@12voltvids

[@dhpbear2]

33:13 - Interesting! Channels 3 and 4 appear to not be playing in reverse!

[@12voltvids]

That's because i recorded them on one of these machines the last time i worked on one.

[@Itsyaboy88]

Do you have a business? If so, how do I get in contact with you to fix mine! 🙏

[@12voltvids]

Contact info is on the main page

[@robinsattahip2376]

Nice repair, impressive figuring that transformer out without a schematic. Thanks. Tascam is professional-grade equipment.

[@BMU5]

Dear please help was plugged 100v to 220v and sure something was damaged by please can you make clear: what cause wrong plug 🔌 for few seconds like such? After wired sound it was taken off. Please anything about to know my further with it

[@12voltvids]

If you plugged a 120 volt device into 240 you have probably burned the power transformer out at a minimum.

[@BMU5]

@ only replace or as well can be repaired? As well can it be changed to 220v somehow?

[@BMU5]

@ can send pictures to email please?

[@BMU5]

@ Appreciate your answer

[@K33f11]

I tried to buy one of these 2 days ago "untested". They go for as much as £500 in working order. I have a feeling this video will be useful someday 😂

[@professorvoluck9311]

I would give anything to have someone with his skill set near me. These videos are second best. I have a large collection of decks and I actually intentionally purchase models that he services in the videos so I have them for reference. It always shocks me that he remembers which screws go where.

[@markmarkofkane8167]

Very interesting.

[@Raptor50aus]

Yes I heard something rolling around inside at 2:03 :(

[@Douglas_Blake_579]

A question... You had access to both pins, why not patch in an inline fuse holder rather than using a thin wire?

[@12voltvids]

Didn't have one on hand and wasn't about to go and buy one. Thin strand will blow if there is a problem. He didn't even want to put a new thermal cutout in cost is an issue here.

[@Douglas_Blake_579]

@@12voltvids Thanks. That makes sense.

[@Synthematix]

Transformers, fuses in disguise... I have a yamaha one of these the minidisc version it takes data MDs and regular 80min discs, has awesome sound quality.

[@Raptor50aus]

That solder sucker is not a good one. My old one takes along time to start to block and very easy to clean. Does not spray anything on boards either. Mine is the "SoldaPullt" brand.

[@12voltvids]

I used to have a small black soldapult and it was good but it vanished from the shop over 30 years ago. Ordered a new one and this is what arrived.

[@NextLevelAutoDiagnosticsLLC]

I had a brand new one (still unused) purchased back in the day. I put it up for local sale and immediately got lowball offers. Finally sold it to a soul for $750.

[@12voltvids]

I got a Teac 334 for free. Well not really free as I did take it as partial payment for repairing a Hammond B3. Wish I made a video of that but the owner wouldn't let me film it in his house.

[@mikemurphy7711]

Can't believe you didn't have an extra screw laying around to put back in cassette deck ass'y. Just because you found only one screw mounted being a wrong doesn't justify a second wrong putting back together. Besides it looks like you bred an extra gold screws or two after taking unit apart.

[@12voltvids]

The deck is held in place from screws that go in from the bottom that holds the cabinet together.

[@mikemurphy7711]

@@12voltvids Okay that's good to know, and yes I do enjoy your videos, many are helpful, as once a broadcast engineer 18yrs.

[@Synthematix]

Transformers, fuses in disguise... I have a yamaha one of these the minidisc version it takes data MDs and regular 80min discs, has awesome sound quality.