Definitely at least one stupid question here (sorry, first pre amp build but somewhat experienced guitar pedal and speaker builder)... bought an 8500 straight from Japan, waited a while to get one from someone in the US (it is out of stock everywhere) but ended up getting impatient, realize that may have been a mistake now.
US and Japanese version are the same, correct? Just use the 110 voltage. Yes, stupid question but i've never built anything that didn't just use 9v, ha.
Is there anyone that could send me an english manual via pdf? if not a japanese manual would via pdf would work, I just have the leaflet and it would be nice to have a pdf so I could put it into google translate if I can't . Not seeing it on the elekit site.
I def. appreciate the help!
US and Japanese version are the same, correct? Just use the 110 voltage. Yes, stupid question but i've never built anything that didn't just use 9v, ha.
Is there anyone that could send me an english manual via pdf? if not a japanese manual would via pdf would work, I just have the leaflet and it would be nice to have a pdf so I could put it into google translate if I can't . Not seeing it on the elekit site.
I def. appreciate the help!
I believe Japan voltage is 100V.
US used to be 110V, 117V, now is usually 120V.
My power ranges from 117V to 123V (centered around 120V).
If your Japanese amp is for 100V, you will need either:
A new power transformer
Or . .
A Buck Transformer (like a 120V to 20V transformer). The 20V secondary in series with your 120V power (Connected Out of Phase), will give 100V out.
Do not try and run a 100V transformer off of 120V, your insurance company will not pay for a new house!
US used to be 110V, 117V, now is usually 120V.
My power ranges from 117V to 123V (centered around 120V).
If your Japanese amp is for 100V, you will need either:
A new power transformer
Or . .
A Buck Transformer (like a 120V to 20V transformer). The 20V secondary in series with your 120V power (Connected Out of Phase), will give 100V out.
Do not try and run a 100V transformer off of 120V, your insurance company will not pay for a new house!
Definitely, first determine if you have a 120VAC transformer. They should not have shipped a domestic unit
outside of Japan, since they are the only country that uses 100VAC. If it actually is a 100VAC transformer,
the amplifier cannot be used here. Do not start assembly until you have the right transformer.
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Thanks for all of the replies, I figured I would get dismissed or made fun of, ha. It definitely seems to be the Japanese transformer (it looks different from all of the pictures on the forum), might be my first costly mistake in DIY I've made. I did buy it off ebay so it was definitely my fault but I'd rather not return it and ship it all the way back to Japan.
Does anyone have a recommendation for a transformer, I don't mind spending a little extra since I did save a bit sourcing it from japan? Would any of the other parts need changed?
Does anyone have a recommendation for a transformer, I don't mind spending a little extra since I did save a bit sourcing it from japan? Would any of the other parts need changed?
I have no experience with the TU8500 preamp but in the TU8600S amp, the transformer
is universal and both 100/200V and 115/230V can be supported.
The transformer in the photo you linked has 6 primary wires so it could be 'universal', and
there seems to be multiple spots for the transformer AC primary connector on the PCB:
https://s3.amazonaws.com/tubedepot-com-static/TU8500_inside.jpg
is universal and both 100/200V and 115/230V can be supported.
The transformer in the photo you linked has 6 primary wires so it could be 'universal', and
there seems to be multiple spots for the transformer AC primary connector on the PCB:
https://s3.amazonaws.com/tubedepot-com-static/TU8500_inside.jpg
Some Options
Denis Hui is correct. Solder the board connector into the CN3 (115 volt) position on the board, see attached picture.
Are you going to build the stock kit or upgrade some parts? I had the loan of a TU8500 for a while that had some Mundorf Supreme (base model) in place of C15, C16 (tube to output jacks) and C11, C12 (phono out to select switch). A worthwhile upgrade at least for C15, C16.
If upgrading, or think you will in the future, move the two small electrolytic caps shown in the attached picture to the opposite side of the board. You may have to lay them down. Use some sleeving or stripped off insulation on the leads. Use sleeving on upgrade caps too and keep upgrade C15, C16 as close as possible towards the back of the board. This MIGHT allow room for an upgrade volume pot.
The filament voltage isn't regulated and the 120+ volts in North America tends to run the filament voltage too high. This is controlled (I believe) with a dropping resistor R61. Don't solder it close to the board to start with. Check the filament voltages and if above 12.6 volts try other resistors with slightly higher resistances until the voltage drops to the 12.0 to 12.6 range.
I've seen Elekits supplied with 2 prong AC cords. If yours has one throw it away and use a 3 prong cord.
Cheers, Steve
Denis Hui is correct. Solder the board connector into the CN3 (115 volt) position on the board, see attached picture.
Are you going to build the stock kit or upgrade some parts? I had the loan of a TU8500 for a while that had some Mundorf Supreme (base model) in place of C15, C16 (tube to output jacks) and C11, C12 (phono out to select switch). A worthwhile upgrade at least for C15, C16.
If upgrading, or think you will in the future, move the two small electrolytic caps shown in the attached picture to the opposite side of the board. You may have to lay them down. Use some sleeving or stripped off insulation on the leads. Use sleeving on upgrade caps too and keep upgrade C15, C16 as close as possible towards the back of the board. This MIGHT allow room for an upgrade volume pot.
The filament voltage isn't regulated and the 120+ volts in North America tends to run the filament voltage too high. This is controlled (I believe) with a dropping resistor R61. Don't solder it close to the board to start with. Check the filament voltages and if above 12.6 volts try other resistors with slightly higher resistances until the voltage drops to the 12.0 to 12.6 range.
I've seen Elekits supplied with 2 prong AC cords. If yours has one throw it away and use a 3 prong cord.
Cheers, Steve
