Re: Only you will be able to see thougth all that resine..solder flux
Clean it up, not short.
Here is bottom view of the bias.
http://60.48.69.81:90/~azmi/bias2.JPG
Clean it up, not short.
Here is bottom view of the bias.
http://60.48.69.81:90/~azmi/bias2.JPG
destroyer X said:
Seems fine your bias board.
Continue working ....because something is wrong.
BUT..install ouput transistors..heatsinks..insulate the ones to the heatsink..install protective resistances in series with plus and minus and check once again.
If not perfect..then continue, because for sure there are errors or defective parts.
Amplifier was tested hundred times..works fine and stable.
relax, work hard....and be happy.
Congratulations!..now you are very near to be happy listening a Dx Corporation nice amplifier.
regards,
Carlos
Continue working ....because something is wrong.
BUT..install ouput transistors..heatsinks..insulate the ones to the heatsink..install protective resistances in series with plus and minus and check once again.
If not perfect..then continue, because for sure there are errors or defective parts.
Amplifier was tested hundred times..works fine and stable.
relax, work hard....and be happy.
Congratulations!..now you are very near to be happy listening a Dx Corporation nice amplifier.
regards,
Carlos
Attachments
Re: Yessssss!...the 2K2 resistance..from colector to base
Hi DX,
Yes its installed
, now i`m checking parts one by one, i want to make sure i can have dx amp it very sure its great amp.
Check tip 41c ... ok
42c ... ok
bd139 ... ok
2n5401 both ... ok
now i`m checking all resistor to make sure it has right value and also my board if got any short
Thanks a lot DX being help me all day i`m happy with it.
continue work... i`ll report here if i got any update.
Regards.
Azmi
Hi DX,
Yes its installed
, now i`m checking parts one by one, i want to make sure i can have dx amp it very sure its great amp. Check tip 41c ... ok
42c ... ok
bd139 ... ok
2n5401 both ... ok
now i`m checking all resistor to make sure it has right value and also my board if got any short
Thanks a lot DX being help me all day
i`m happy with it.continue work... i`ll report here if i got any update.
Regards.
Azmi
destroyer X said:
Well... i am working too...preparing an amplifier to my daugther
So....you go working in your amplifier and old uncle will work into his own amplifier.
The transformer is beeing made once again... the new one will come with 110 and 220 inputs... you see there's no transformer inside..for a while only.
Go searching...soon you will find.
regards,
Carlos
So....you go working in your amplifier and old uncle will work into his own amplifier.
The transformer is beeing made once again... the new one will come with 110 and 220 inputs... you see there's no transformer inside..for a while only.
Go searching...soon you will find.
regards,
Carlos
An externally hosted image should be here but it was not working when we last tested it.
DHR Turbo...
Hi... Sir Carlos thanks for your rEply..... You Means the DHR is Better t0 Use Mid Fequency ?
Because y0u said the high frequency and also some mid range
frequency ( voices ) I have a sound system But im not a satisfied my amp to drive a Subwoofer my amp is BOM PO3 p0wer Amplifier 2 fairs
of 2SA1301 and 2SC3280 a channel... s0 i need a s0me more power amp to drive a subwoofer....
Hi... Sir Carlos thanks for your rEply..... You Means the DHR is Better t0 Use Mid Fequency ?
Because y0u said the high frequency and also some mid range
frequency ( voices ) I have a sound system But im not a satisfied my amp to drive a Subwoofer my amp is BOM PO3 p0wer Amplifier 2 fairs
of 2SA1301 and 2SC3280 a channel... s0 i need a s0me more power amp to drive a subwoofer....
The DHR Turbo is good for bass, midrange and treble
To use it only for bass you will be loosing, wasting, trowing out, a lot of good quality audio.
Was not made for bass..it is not a subwoofer amplifier.
The use of this amplifier, only for bass is a bad use...it is alike to use a good, modern, confortable and expensive car, alike a Mercedes Benz or a BMW, to transport stones, bricks and sand for home construction..... to construct buidings we use truck.
The soft suspension you have into a Mercedes Benz, the low internal noise you have into a BMW and leather seats will be damage doing such kind of job...all those features will be lost when doing such kind of work.
You need a dedicated amplifier..something made for bass only.
It is better to modify your own amplifier, the one you have, for bass reproduction, including more output pairs , increasing supply voltage, increasing the speaker output impedance including more speakers into the system.
The bass amplifier is a result of a design that used other kind of decisions while creating it..... DHR Turbo, and other amplifiers i have made, had not the needed decisions during creation stages to be used as a bass amplifier.
Much better than increase amplifier power is to increase system's efficiency...good speakers together good speaker enclosures can produce deep, nice and strong bass with 30 watts or less...so... the need of high power, enormous transformers, a lot of output transistors is a need when we have NO efficient speakers... the bad ones needs a lot of power to move.
The reason we have so many high powered amplifiers (more than 50 watts RMS in my subjective point of view) is because the enormous majority of speakers you find are not good.
Real good speakers reach maximum excursion (compliance) into the diafragm with 5 volts.....so... those ones, with something alike 3 watts will do the job.... and better than a thousand watts amplifier connected to a BAD 1000 watts amplifier.
I really think you should scan our forum.... searching for high powered amplifiers, those ones published as 1 kw or more.... those ones will be more correct to your power needs.
I will not modify my amplifier to subwoofer use, or to bass only use.
The exception is the Trust Bass..but that one is low power and was not tested , only created into simulator... and this means nothing or half of nothing...was not built and listened.
The Trust built and listened and tested was a full range.... all audio bandwidth...not only bass.
Here you have the DHR Turbo thread:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=124931&perpage=25&pagenumber=1
To use it only for bass you will be loosing, wasting, trowing out, a lot of good quality audio.
Was not made for bass..it is not a subwoofer amplifier.
The use of this amplifier, only for bass is a bad use...it is alike to use a good, modern, confortable and expensive car, alike a Mercedes Benz or a BMW, to transport stones, bricks and sand for home construction..... to construct buidings we use truck.
The soft suspension you have into a Mercedes Benz, the low internal noise you have into a BMW and leather seats will be damage doing such kind of job...all those features will be lost when doing such kind of work.
You need a dedicated amplifier..something made for bass only.
It is better to modify your own amplifier, the one you have, for bass reproduction, including more output pairs , increasing supply voltage, increasing the speaker output impedance including more speakers into the system.
The bass amplifier is a result of a design that used other kind of decisions while creating it..... DHR Turbo, and other amplifiers i have made, had not the needed decisions during creation stages to be used as a bass amplifier.
Much better than increase amplifier power is to increase system's efficiency...good speakers together good speaker enclosures can produce deep, nice and strong bass with 30 watts or less...so... the need of high power, enormous transformers, a lot of output transistors is a need when we have NO efficient speakers... the bad ones needs a lot of power to move.
The reason we have so many high powered amplifiers (more than 50 watts RMS in my subjective point of view) is because the enormous majority of speakers you find are not good.
Real good speakers reach maximum excursion (compliance) into the diafragm with 5 volts.....so... those ones, with something alike 3 watts will do the job.... and better than a thousand watts amplifier connected to a BAD 1000 watts amplifier.
I really think you should scan our forum.... searching for high powered amplifiers, those ones published as 1 kw or more.... those ones will be more correct to your power needs.
I will not modify my amplifier to subwoofer use, or to bass only use.
The exception is the Trust Bass..but that one is low power and was not tested , only created into simulator... and this means nothing or half of nothing...was not built and listened.
The Trust built and listened and tested was a full range.... all audio bandwidth...not only bass.
Here you have the DHR Turbo thread:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=124931&perpage=25&pagenumber=1
Here is a DX corporation amplifier.
DX likes to recycle, so we started with a Sansui 2000 receiver from the 1970s.
The Sansui looked very nice- separate bass and treble for each channel, but for $5.00 its getting taken home and taken apart to hold the DX.
The back panel was redone for an amplifier and to fit the large heatsinks that luckily will just fit exactly into the case.
All connectors are new except for fuse holders.
Fuse holders have not changed in 30 years.
The DX is working, biased for each emitter resistor to have about 65 mA across it.
Just gets a little bit warm, I will probably increase bias.
Charlie does not care- he wants to go for a walk and chase lizards.
I have replaced gain resistors with higher values to reduce the gain which Carlos says was too high
Power supply is 4x15,000 uF capacitors with no CRC filtering. Xfo is 25-0-25 and 500 VA "rescued" from another project (trash bin).
There is no hum.
DC offset is < 20 mV.
And it turns out everything just fits into the Sansui. I am going to get a fancy new front panel and this will look very nice.
How does it sound- not sure, just got it working and will try with 'real' speakers after I am sure it will not blow up on me.
DX likes to recycle, so we started with a Sansui 2000 receiver from the 1970s.
An externally hosted image should be here but it was not working when we last tested it.
The Sansui looked very nice- separate bass and treble for each channel, but for $5.00 its getting taken home and taken apart to hold the DX.
The back panel was redone for an amplifier and to fit the large heatsinks that luckily will just fit exactly into the case.
An externally hosted image should be here but it was not working when we last tested it.
All connectors are new except for fuse holders.
Fuse holders have not changed in 30 years.
The DX is working, biased for each emitter resistor to have about 65 mA across it.
Just gets a little bit warm, I will probably increase bias.
Charlie does not care- he wants to go for a walk and chase lizards.
An externally hosted image should be here but it was not working when we last tested it.
I have replaced gain resistors with higher values to reduce the gain which Carlos says was too high
Power supply is 4x15,000 uF capacitors with no CRC filtering. Xfo is 25-0-25 and 500 VA "rescued" from another project (trash bin).
There is no hum.
DC offset is < 20 mV.
And it turns out everything just fits into the Sansui. I am going to get a fancy new front panel and this will look very nice.
How does it sound- not sure, just got it working and will try with 'real' speakers after I am sure it will not blow up on me.
Beautifull...do it!....yeah...yesssss!..... great!
New slide movie uploaded to youtube fellows.
Brian have asked pictures.... so, here they are...more than hundred and all them High Definition..... 1700 by 1000 pixels.
enjoy...it is for free!
http://www.youtube.com/watch?v=d52ZrS14WdI
Music is African Beat, by Bert Kaempfert...recorded with tube equipment down the sixties (1960 to be precise)
regards,
Carlos
New slide movie uploaded to youtube fellows.
Brian have asked pictures.... so, here they are...more than hundred and all them High Definition..... 1700 by 1000 pixels.
enjoy...it is for free!
http://www.youtube.com/watch?v=d52ZrS14WdI
Music is African Beat, by Bert Kaempfert...recorded with tube equipment down the sixties (1960 to be precise)
regards,
Carlos
An externally hosted image should be here but it was not working when we last tested it.
Plastic
I used to use the cases from floppy disks, just remove the disk on the inside, but they were not solid enough. So years ago I bought a piece of "ABS Plastic Sheet" on Ebay. This is a very thick plastic sheet with a coarse finish ("haircell textured") on one side and smooth glassly/ glossy finish on the other.
Auction for ABS Plastic Sheet
I place the rough side on the inside, and cut to size with anything- dremel, knife, scizzors, drill, tin snips, etc... I drill holes where the old screws were and mount behind using the original screws.
A standard cutting disk with a Dremel will cut this easily on low speed. Note that if you try scizzors that because this plastic is very thick it will leave a white stress mark near the cut so you have to make sure to cut a small amount larger than what will be visible. Dremel cutting leaves no mark. But the point is that this stuff is sturdy, easy to cut shape and drill. And its insulating.
Here is the DX II backside cut with tin snips (note white marks)-
Here is my Pass F5 backside cut with a Dremel-
Here is the DX II on the outside, note the mistake/ white mark from cutting with a tin snip...
too close to the visible part near the lower right corner of 'antenna' where the "FM" part is.
And here is the Pass F5 on the outside
This stuff actually looks very nice and professional, better than you can see in the pics. And its sturdy enough to hold a pair or more of speaker terminals.
If you have spent as much time as I have filing metal for your cases, you will love how easily this stuff can be shaped with a file. Its a pleasure to work with!
dudaindc said:Nice job lgreen!
***
Could you please post a picture of the inner side of the back panel? I would like to see how you blocked/sealed the unused openings.
Thanks!
I used to use the cases from floppy disks, just remove the disk on the inside, but they were not solid enough. So years ago I bought a piece of "ABS Plastic Sheet" on Ebay. This is a very thick plastic sheet with a coarse finish ("haircell textured") on one side and smooth glassly/ glossy finish on the other.
Auction for ABS Plastic Sheet
I place the rough side on the inside, and cut to size with anything- dremel, knife, scizzors, drill, tin snips, etc... I drill holes where the old screws were and mount behind using the original screws.
A standard cutting disk with a Dremel will cut this easily on low speed. Note that if you try scizzors that because this plastic is very thick it will leave a white stress mark near the cut so you have to make sure to cut a small amount larger than what will be visible. Dremel cutting leaves no mark. But the point is that this stuff is sturdy, easy to cut shape and drill. And its insulating.
Here is the DX II backside cut with tin snips (note white marks)-
An externally hosted image should be here but it was not working when we last tested it.
Here is my Pass F5 backside cut with a Dremel-
An externally hosted image should be here but it was not working when we last tested it.
Here is the DX II on the outside, note the mistake/ white mark from cutting with a tin snip...
too close to the visible part near the lower right corner of 'antenna' where the "FM" part is.
An externally hosted image should be here but it was not working when we last tested it.
And here is the Pass F5 on the outside
An externally hosted image should be here but it was not working when we last tested it.
This stuff actually looks very nice and professional, better than you can see in the pics. And its sturdy enough to hold a pair or more of speaker terminals.
If you have spent as much time as I have filing metal for your cases, you will love how easily this stuff can be shaped with a file. Its a pleasure to work with!
Alcohol finished in my home.
So... let's give it a bath with Wiskie!
Hic!
So... let's give it a bath with Wiskie!
Hic!
An externally hosted image should be here but it was not working when we last tested it.
Oh!.... wiskie is not cleaning!
Ship!!!..... board is alike a ship in the ocean..floating in alcohol but wiskie is not working,.
Ship!!!..... board is alike a ship in the ocean..floating in alcohol but wiskie is not working,.
An externally hosted image should be here but it was not working when we last tested it.
Tomorrow i will be listening..i know that my boards are not pretty
But they are huge and works!
Tomorrow.
bye!
Carlos
But they are huge and works!
Tomorrow.
bye!
Carlos
An externally hosted image should be here but it was not working when we last tested it.
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