Tech questions about Voltage & Frequency - Need some SERIOUS help please!

[cjacek]

I touched on this issue a little while ago but I'm still not 100% resurred ... Let me ask again: Would there be any problems whatsoever, provided a voltage transformer is used, with running a TEAC 3440, TASCAM 388, TASCAM 244, TASCAM M30 and TEAC 2A mixers on European voltage or to be more specific 230/240V / 50Hz ? Looks like the move to Europe is most probable now and (1) I have to take the gear with me but (2) I don't want to overheat or damage it in any way. Please advise and I really do need some definitive answers on this topic.

Thanks!

Daniel

 

[arjoll]

I touched on this issue a little while ago but I'm still not 100% resurred ... Let me ask again: Would there be any problems whatsoever, provided a voltage transformer is used, with running a TEAC 3440, TASCAM 388, TASCAM M30 and TEAC 2A mixers on European voltage or to be more specific 230/240V / 50Hz ? Looks like the move to Europe is most probable now and (1) I have to take the gear with me but (2) I don't want to overheat or damage it in any way. Please advise and I really do need some definitive answers on this topic.

Hi Daniel

1. You will need to get a step-down autotransformer to drop the 230v nominal mains voltage to 120v. Check some electronics store websites in the country you're heading to to confirm that you can get one - they shouldn't be hard to get (we can get a whole range in NZ).

2. Your mixers will be fine. They will all use a linear power supply and the transformer will be able to handle the different frequency.

3. As long as your recorders use DC motors you will be fine. If they use AC - say for the spool motors - you will need to check with Tascam, or scan and email over the circuit diagrams if you have them handy - andrew@onlinecomputers.co.nz - and I'll have a look to see how they're run.

Of course, if you moved to NZ instead you'd be able to just drop the gear in and I'd check it for you

Cya
Andrew

 

[cjacek]

Hi Daniel

1. You will need to get a step-down autotransformer to drop the 230v nominal mains voltage to 120v. Check some electronics store websites in the country you're heading to to confirm that you can get one - they shouldn't be hard to get (we can get a whole range in NZ).

2. Your mixers will be fine. They will all use a linear power supply and the transformer will be able to handle the different frequency.

3. As long as your recorders use DC motors you will be fine. If they use AC - say for the spool motors - you will need to check with Tascam, or scan and email over the circuit diagrams if you have them handy - andrew@onlinecomputers.co.nz - and I'll have a look to see how they're run.

Of course, if you moved to NZ instead you'd be able to just drop the gear in and I'd check it for you

Cya
Andrew

Man, thanks Andrew! I'll try and find any paperwork/diagrams which may help .. Good thing I didn't sell off my scanner yet so I'll just use that for sending stuff over .. I'll let you know ...

As far as TASCAM, the guy told me the recorders all use a DC capstan motor and should have no issues whatsoever .... I also personally looked at the reel (spooling) motors on the 3440 and it said AC 50/60Hz. I often wondered HOW TEAC Japan designed the machines with relation to voltage etc .... I mean, weren't all of the machines designed to be run under any voltage/frequency situation ? I mean at least the most recent from the late 70's into the 80's and so on .... They had to use the same motors, power supplies etc .. didn't they ?

Tell me a little more about mixers for example. I know that if I change the voltage then that would be fine but HOW do the electronics handle the 50/60 Hz variations ?

Thanks again Andrew and I'll take a look at my documentation - I'm sure I have the schematics .....

Daniel

 

[A Reel Person]

You could send the gear to me, & I'll hold on to it for'ya!

......................

 

[evm1024]

Should be OK

Hi,

I'm looking throught the schematic of my 3440. The capstan moter is DC so it is good. The only issue that I can see is that the FF/RW motors would run slower on 50 Hz but I do not think that that is any issue. Just run the step down transformer.

The various versions have different transformers and some different values to bypass caps (mostly in voltage ratings) that are not an issue with the step down transformer.

The general export model shows voltage selector and freq selector switches to allow adjustments. You may want to look inside to see it they are present. (The Canadian and US model are the same by my docs).

I have a errand to run now but I will track down the 60/50 Hz switch function and get back to you.

In short, onthe 3440 you should be good to go.

Regards!

 

[evm1024]

Bypass caps

OK,

I see on the schematic that the 50/69 Hz selector adds in parallel a 1.5 uF cap to the existing 7 uF caps on the FF and RW motors. You should be fine with out them on your 3440.

Regards

 

[arjoll]

As far as TASCAM, the guy told me the recorders all use a DC capstan motor and should have no issues whatsoever .... I also personally looked at the reel (spooling) motors on the 3440 and it said AC 50/60Hz. I often wondered HOW TEAC Japan designed the machines with relation to voltage etc .... I mean, weren't all of the machines designed to be run under any voltage/frequency situation ? I mean at least the most recent from the late 70's into the 80's and so on .... They had to use the same motors, power supplies etc .. didn't they ?

From what I've seen of various schematics there were often different versions - usually a different power supply module, and possibly control circuitry if they use a synchonous (AC) capstan motor. Your Teac would have had a different power supply, my Akai has a different power supply and different value caps in the motor control circuitry.

The models we see in NZ are generally either the European or 'general export' models - these use a different mains transformer if they use a linear power supply, either a 230v one (EU/AU versions) or one with two 120v windings and a switch to select them in parallel (120v) or series (240v).

Tell me a little more about mixers for example. I know that if I change the voltage then that would be fine but HOW do the electronics handle the 50/60 Hz variations ?

The internals of your mixer are probably entirely DC - no AC motors or anything. The only thing that might run on AC are the VU meter lamps, if it has them. Voltage is more critical than frequency - the lamps don't care, and the mains transformer should be fine.

Cya
Andrew

 

[cjacek]

scan and email over the circuit diagrams if you have them handy - andrew@onlinecomputers.co.nz - and I'll have a look to see how they're run.

Andrew,

I was able to unpack all of the schematics for all of my gear. Question: What specifically do I scan and send you ? There's lots of stuff so I need to know which parts. Lead me by the hand here.

Thanks again!

Daniel

 

[cjacek]

evm1024 : Thanks so much for looking into this issue for me.

A Reel Person : Hey, Dave .. I know you'd take care of my gear so I would have no problem with that.

 

[arjoll]

I was able to unpack all of the schematics for all of my gear. Question: What specifically do I scan and send you ? There's lots of stuff so I need to know which parts. Lead me by the hand here.

Just the circuit diagrams for the power supply section of your mixer (probably one will be ok, I'm guessing that even between series there's probably not too much difference).

How many pages are we talking for the decks? If you compare them first (power supply sections and anything - reel motors etc - running from AC before a rectifier). If you scan then drop to a 16 colour greyscale GIF the files shouldn't be too huge - 150dpi would probably be fine. I have no issues with file size, as long as the total email is < 10 MB or so.

I'm guessing you're about 18 hours behind NZ? (UTC-6)? I'll check my email up until around 10pm NZST (1000 Sunday UTC) and then from around 8:30am Monday (2030 Sunday UTC)

Cya
Andrew

 

[cjacek]

Just the circuit diagrams for the power supply section of your mixer (probably one will be ok, I'm guessing that even between series there's probably not too much difference).

How many pages are we talking for the decks? If you compare them first (power supply sections and anything - reel motors etc - running from AC before a rectifier). If you scan then drop to a 16 colour greyscale GIF the files shouldn't be too huge - 150dpi would probably be fine. I have no issues with file size, as long as the total email is < 10 MB or so.

I'm guessing you're about 18 hours behind NZ? (UTC-6)? I'll check my email up until around 10pm NZST (1000 Sunday UTC) and then from around 8:30am Monday (2030 Sunday UTC)

Cya
Andrew

I'll have to check the diagrams more closely and will find the appropriate ones to scan. It's 1:26 am here and I'll do the finding and scanning later on today (Sunday) and will try to upload the files after that. Please give me a day or two. Again, thanks Andrew for taking the time.

~Daniel

 

[cjacek]

I'm still working on the scans but here's a question/concern: I was told that any unit (mixer, recorder etc ..) using a "conventional psu" with a line frequency transformer will draw more magnetising currrent @ 50Hz compared to 60Hz. If this is the case with my gear then it may experience problems with the transformer over-heating. What do you think ?

 

[arjoll]

Check with Tascam

I'm still working on the scans but here's a question/concern: I was told that any unit (mixer, recorder etc ..) using a "conventional psu" with a line frequency transformer will draw more magnetising currrent @ 50Hz compared to 60Hz. If this is the case with my gear then it may experience problems with the transformer over-heating. What do you think ?

OK, I must admit I'd never considered that, having dealt exclusively with 50Hz gear up until now.

Check http://www.soundonsound.com/sos/Jul03/articles/mainsproblems.asp (I found the page slow, if it doesn't load there's a cache at http://66.102.7.104/search?q=cache:...s.asp+50hz+60hz+transformer+magnetising&hl=en which explains the issues surrounding operating your gear in Europe.

It looks like it depends how cheap Teac went on the transformers in your gear when it was produced. We might be able to tell this from the schematics - especially if they show multiple power supplies and we can find out info about the ratings of the transformers. If you google the part numbers you might be able to track down specs, especially if Teac used OEM transformers.

Zap over those schematics anyway. Note that voltage depends on where you are going in Europe - the UK traditionally had 240v, places like Italy had 220v.

 

[cjacek]

OK, I must admit I'd never considered that, having dealt exclusively with 50Hz gear up until now.

Check http://www.soundonsound.com/sos/Jul03/articles/mainsproblems.asp (I found the page slow, if it doesn't load there's a cache at http://66.102.7.104/search?q=cache:...s.asp+50hz+60hz+transformer+magnetising&hl=en which explains the issues surrounding operating your gear in Europe.

It looks like it depends how cheap Teac went on the transformers in your gear when it was produced. We might be able to tell this from the schematics - especially if they show multiple power supplies and we can find out info about the ratings of the transformers. If you google the part numbers you might be able to track down specs, especially if Teac used OEM transformers.

Zap over those schematics anyway. Note that voltage depends on where you are going in Europe - the UK traditionally had 240v, places like Italy had 220v.

Thanks for the links Andrew. I'll keep trying them 'cause they were indeed slow to load. Anyway, here's a link to download a ZIP file (all jpeg) of the scans:

DOWNLOAD

Unfortunately I had no power schematics for one of my mixers, the teac 2a .... Others are all there though .....

Andrew, I think it would be cool if we kept this thread going with all this great tech info so please feel free to reply here. Thanks again my friend!

~Daniel

 

[arjoll]

Thanks Daniel.

I'll do a bit more research on most of this tomorrow - will call a service tech friend of mine.

Do you have part numbers for the transformers in these units? Would be interesting to see if there are more specs published for these. Can't find detail on the M30 unfortunately. Looking at the 3440 I would add those 1.5uF caps shown when you go to 50Hz.

Sorry this hasn't all been quite as straightforward as it should be. Will get back to you tomorrow (NZ time) with more info...

Cya
Andrew

 

[arjoll]

Thanks for the links Andrew. I'll keep trying them 'cause they were indeed slow to load.

Just realised the second one is a Google cache which is probably a lot more local to me than you! You should be able to get to this by Googling the following keywords:
50hz 60hz transformer magnetising
and then going to the cached copy of the Sound On Sound article.

 

[cjacek]

Andrew,

I was able to read that sound on sound article - most interesting! Thanks for the link.

I will try to locate the part numbers for the power supplies and will get back to you asap!

~Daniel

 

[arjoll]

Should be fine

I have checked with an electronics technician with about 30ish years experience, including 10+ years at BCNZ before they split the radio and television parts off.

In his opinion it should not be a problem, especially on well designed equipment such as Teac/Tascam recording gear. It would have to be a very under-spec'd transformer which is only marginal on 60 Hz to have any real problems on 50 Hz.

Reading through the articles I'd say the main thing would be to listen out for dramatically increased transformer hums in your gear - they are one of the first indications of trouble and if you do notice them it won't be too late to pull the plug with no harm done.

I would definately add the caps on the reel motors of your 3440 (I'm guessing they do some power factor manipulation).

Hope this is some help. Would be interesting to find out what the cost of the AU/UK version of the transformer is.

Cya
Andrew

 

[cjacek]

I have checked with an electronics technician with about 30ish years experience, including 10+ years at BCNZ before they split the radio and television parts off.

In his opinion it should not be a problem, especially on well designed equipment such as Teac/Tascam recording gear. It would have to be a very under-spec'd transformer which is only marginal on 60 Hz to have any real problems on 50 Hz.

Reading through the articles I'd say the main thing would be to listen out for dramatically increased transformer hums in your gear - they are one of the first indications of trouble and if you do notice them it won't be too late to pull the plug with no harm done.

I would definately add the caps on the reel motors of your 3440 (I'm guessing they do some power factor manipulation).

Hope this is some help. Would be interesting to find out what the cost of the AU/UK version of the transformer is.

Cya
Andrew

WOW! Thanks Andrew! Thank you for looking into this for me .... Yeah, that's pretty much the answer the tech guys at TASCAM gave me and also a TASCAM service centre here in town ... that the transformers are large and well built in those machines (reels and mixers) so the 50/60 hz won't really matter. They mentioned that it all gets turned into DC anyway so it really isn't an issue, the whole hz thing. They said the gear can handle it no problem. Btw, sorry for not getting those part #'s to you but I think we've concluded somethin' here without the need to "dig" further ....

~Daniel