I never thought I'd see you saying that!
Well, I can put my hand on the PT of my Chinese-based amp also, and it has the through bolts.....Here is mine. No need for measurements, after the whole day of playing.
I never thought I'd see you saying that!
...to tell that overheating is less than 30 degrees Celsium. I just can't find my IR camera, I misplaced it somewhere.
So, what's the problem then?
You told me there was a 'shorted turn' problem because of the way I'd mounted the transformer!
Anyway, it's something for me to keep in mind for future builds. Sometimes old transformers are missing the fiber washers, or they are disintegrating. Up to now, I've just replaced them with (steel) spur or lock washers.
So, thanks for that info!
You may have found this thread: Boyuu EL34 A9 Tube Amp
Lots of help here at diyaudio!
Enjoy the project!
What was the cost in CAD, to your door? (Just curious to see how prices have changed since I bought an amp kit....)
Lots of help here at diyaudio!
Enjoy the project!
What was the cost in CAD, to your door? (Just curious to see how prices have changed since I bought an amp kit....)
Thank you VG: will port over to that thread - I did actually see it but it seemed too large and cumbersome to wade through all the mods etc. when I really just want to first build as-is first and then mod from there. Already got the on-off switch and volume switch in hand to take to Queale (Sp?) electronics tomorrow to see if I can find something better as they are Cheeeeeeap junk IMHO. Was really impressed with the case though. Here is the tally (shipping free): EL34 Tube Amplifier DIY Kits Class A Single End EL34 Integrated Amplifier Kits | eBay
It did cost me $31.50 in courier fees when it arrived today but I got it super-quick so worth it - wasn't expecting to get it until the new year really (as per the shipping estimate on ePray) so pleasant surprise when it arrived today. Now I have something to do for the holiday season. I find the documentation absolutely sucks and I have a myriad of these little daughter board type chummies that I am trying to figure out orientation and how they actually integrate into the build...
First thing to research is pin orientation on the tube mounts relative to the case
It did cost me $31.50 in courier fees when it arrived today but I got it super-quick so worth it - wasn't expecting to get it until the new year really (as per the shipping estimate on ePray) so pleasant surprise when it arrived today. Now I have something to do for the holiday season. I find the documentation absolutely sucks and I have a myriad of these little daughter board type chummies that I am trying to figure out orientation and how they actually integrate into the build...
First thing to research is pin orientation on the tube mounts relative to the case
I've never found anything except expensive (price) but very poor quality parts at Queale (Interior Electronics) here in Victoria. I bought some switches and pots there when I first started building amps 15 yrs ago and the quality hasn't improved since then.
My advice would be to order from Digikey.ca or Mouser.ca - they both have very fast flat rate shipping from the US to Canada, without brokerage and other add-on charges, in my experience. I've received Digikey orders 36 hrs after ordering online. The only 'trick' is to find exactly what you need from the millions of items available. PartsExpress is also a possible source for some parts. EBay is OK for some jacks and terminals if you know exactly what quality you are looking for. For caps and resistors, justradios in Toronto is good for standard quality parts.
And, if you are keen to spend a lot of money for dubious improvements in sound, there are plenty of 'boutique' parts sellers, which sometimes have actual good-quality parts mixed in with the snake-oil.
That said, you may well find that the parts in your kit are OK- sometimes it's hard to judge by looks alone.
What about a soldering station, solder, tools, etc... are you all set for that? Don't try building without a good iron as it will make everything more difficult.
Tube pinouts are always from the bottom of the tube, as far as I know.First thing to research is pin orientation on the tube mounts relative to the case
If you need anything specific (advice or 'local knowledge') you can send me a message here. Just click on my user name. You have disabled private messaging on your profile?
Some of the comments on local retail outlets, etc are probably not of interest to most readers of this thread.
Also, it might be an idea to either add your Boyuu A9 build experiences to that existing thread, or start a new thread....
Yes, for 220-240V in the outlet. The switch in the kit and on the picture is different from what was drawn, it is single pole.
Here it is on Taobao, with different transformer orientation, $72 including a bottom lid.
??????6P3P??????????????6p3p?????-???
Here it is on Taobao, with different transformer orientation, $72 including a bottom lid.
??????6P3P??????????????6p3p?????-???
DonQ,
Just a quick look at Post #3 schematic, and your wiring diagram in post # 70 are not the same.
There are some important dissimilarities.
One of the differences is in the negative feedback circuit and parts.
Perhaps the output transformers are different, and require different negative feedback circuit and parts values to keep the amp stable.
Just a quick look at Post #3 schematic, and your wiring diagram in post # 70 are not the same.
There are some important dissimilarities.
One of the differences is in the negative feedback circuit and parts.
Perhaps the output transformers are different, and require different negative feedback circuit and parts values to keep the amp stable.
navydiver,
On your schematic in post # 64, do not forget that the input tube pin 4 is left unconnected (not good).
How about a couple of 100 Ohm grid stopper resistors, one on pin 1, and one on pin 4 (connect them right at the tube socket tabs. Then connect the other ends of the 100 Ohm grid stoppers to the 470k and wiper of the volume control.
On your schematic in post # 64, do not forget that the input tube pin 4 is left unconnected (not good).
How about a couple of 100 Ohm grid stopper resistors, one on pin 1, and one on pin 4 (connect them right at the tube socket tabs. Then connect the other ends of the 100 Ohm grid stoppers to the 470k and wiper of the volume control.
Yes...I have Googled for this kit and have run across various versions with variations, one didnt even have the feedback at all...my schematic has a 2K, another layout had a 10K...
Some versions move the supply caps on either side of the choke...
Ergo my question on who actually has one running, LOL.
Guys here in the states,
Banggood.com is selling this kit, or something real, real, similar, for a pretty decent price right now - I just picked one up for < $117 including shipping and insurance from the U.S. warehouse, after a $10.00 discount coupon. They only had ten left, so if you want one, I would not hesitate ...
Not sure what I will do with it, experiment I guess, hard to pass up at that price ...
edit: I'm GUESSING this is a 120 volt line transformer; but prospective purchasers might need to be prepared to deal with either a 120 or 230 v xfmr ( I am ) ...
6p3p tube amplifier diy amplifier class a single-end tube amplifier kit Sale - Banggood.com
Banggood.com is selling this kit, or something real, real, similar, for a pretty decent price right now - I just picked one up for < $117 including shipping and insurance from the U.S. warehouse, after a $10.00 discount coupon. They only had ten left, so if you want one, I would not hesitate ...
Not sure what I will do with it, experiment I guess, hard to pass up at that price ...
edit: I'm GUESSING this is a 120 volt line transformer; but prospective purchasers might need to be prepared to deal with either a 120 or 230 v xfmr ( I am ) ...
6p3p tube amplifier diy amplifier class a single-end tube amplifier kit Sale - Banggood.com
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Consider changing it to solid state rectifier. With that you, you have one more socket and higher B+ to work with. ie: Screen voltage regulation, CCS, driver and etc.
It's going to be pretty far down my project list ...
Once I get a look at the chassis punchings, I can get a better idea of what to do with it, and which of my OPT's / PT's can fit with out a lot of drama, if I don't want to use what comes with it.
I was actually thinking of some 6DZ7's, in a mini push pull amp, with MOSFET split load, but it could wind up as anything.
Once I get a look at the chassis punchings, I can get a better idea of what to do with it, and which of my OPT's / PT's can fit with out a lot of drama, if I don't want to use what comes with it.
I was actually thinking of some 6DZ7's, in a mini push pull amp, with MOSFET split load, but it could wind up as anything.
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