Peleus
-
Posts
32 -
Joined
-
Last visited
Content Type
Profiles
Forums
Events
Posts posted by Peleus
-
-
6 hours ago, Pars said:
For many device series types, the N and P are not going to match well. If you can get more devices at a reasonable price, that is always best. Where are you purchasing these devices from? A known supplier? I guess my point is, are they genuine devices? A lot of fakes out there (ebay, aliexpress, dalbani, etc.)
I got this DCA75 Pro from digikey. I think it can not be fake one. So, How close the two hfe values of these 15030/15031 are? Can you give me some values as a reference?
-
Hi, Guys,
I'm working on my CFA2 project.
I've got a matching MJF15030/15031 question : How nice is the matching?
I had a Peak DCA-75 to match these two BJTs, the result is horrible. The hfe values of One bjt are most from 280-290, the other are from 70 to 120. It is seem not nice enough, right?
So, how nice is the close enough matching of these two BJT? May I need to buy more bjt to get nice matching?
-
Hi~
I just finished the GR regulator for my SONY PCM D50.
This regulator is from my friend who is the original designer of GR regulator.
The schematic of GR regulator is not new at all; however, the parts of the GR regulator is very very crucial.
So, check it out and find some awesome points of this new version of GR regulator.
-
Hi guys,
Guess what? I've solved the humming problem! hu....Finally.
I asked the transformer supplier, and he said the transformer unlikely the source of problem. He suggested me try to ground the heater line.
After doing some research on the google, I choose this solution, but mod little due to I don't have the pot now.
This is my solution as the below picture showed.
Great, No more hum in the low resistance on-ear headphone.
And More, NO rebuild and major modification again. Thanks God!
And, Thanks you all guys and your suggestions.
Sincerely,
Peleus, Taipei, Taiwan
-
6 hours ago, Skooby said:
Thumbs-up on the Metcal! Old tubes sometimes are humming too.
Thanks, it is old and used machine, but still very, very, useful and reliable one.
Old tubes humming...umh...I think that I may buy some tubes to try. Luckily, the tube is cheap and easily found in Taiwan.
2 hours ago, jose said:Before leaving it, why do not you separate the trafo?
Well...It may help to confirm the source of humming, but I really need a One-Chassis headphone amp.
2 hours ago, spritzer said:Yup and swap out the tubes. Is the shield on the transformer connected to ground? Ideally it should be earthed...
Yes, the shield is grounded. And, Thanks your earthed chassis advice.
8 minutes ago, n_maher said:I think you should carefully consider how disappointing it would be to tear it down, rebuild it, and then find the same problem still exists since you didn't bother to try to trace the source this time.
Yup, You are right. I really be disappointed about the result.
You teach me a good advice that figuring out the problem first.
Thank you!
-
Hi,
After 3 hrs hard work, I rewired the ground loop. Will, it is still not work!!!!
I found this amp is good for the on-ear headphone, although the Huge hum. For the over-ear phone with high resistance, the power is not enough, but no Hum at all.
I...give up, and plan to tear down the tubes part, and to re-layout, from lay-down form to stand-up form.
And, don't forget to earth the chassis.
What a mess!
-
Hi, guys,
Thanks for all your advises and suggestions. Our global audio diy community is always warm and encouraged.
Maybe I provide too little pictures of the amp to give you clear picture of the amp.
It's not virtual grounding, It is designed as single-end amp. And, I made a star grounding in the up-left corner of the above picture.
It's may not clearly to look the grounding due to I used the black wire as grounding line.
After a day working, The Neutrik phone socket may have contacting problem, the sound of one channel is unstable. The layout of grounding wiring will be changed.
Two boxes? It is not may original making idea. I need a small headphone amp, not a huge and expensive one.
Now, it is Chinese New Year in Taiwan. So, I don't have time to work on this amp.
The more pictures may help your guys to understand, here it is...
-
It's done !
It's low B+ voltage version Aikido Hybrid headphone amp designed by John Broskie.
However, I replaced the tube, 6GM8, with 12FM6, due to the price of the former is so high to me.
Now, I still fight for terrible hum issue !
-
Sorenb, Thank you very much! I've got the boards just a minute ago.
And, It is quite awesome to me that my name is printed on the the envelope in exactly correct Chinese!
Awesome! How did you do that? I didn't tell you my Chinese name in English, not even in Chinese!
Cool, man!
-
1
-
-
18 hours ago, sorenb said:
I'd prefere to wait with people paying until we get firm quotes and are ready to make the order.
Shipping depends on your individual preferences. Some wants tracking/sign-off, others don't care and go for regular mail.
1kg for Taiwan using UPS is ~55USD, regular mail is ~15USD.So far there has been no loss of packages using either service ( ~100 packages in total for the past three group buys).
A few packages was on its way for weeks before showing up using regular mail, but that is about it.See! Thanks, sorenb.
-
Thanks, sorenb.
So, may I pay now? How much is the shipment fee?
I live in Taiwan, and what shipment you will use? UPS? DHL? or something else?
-
Thanks sorenb, I need four Carbon PCB.
May I pay by PayPal?
-
Hi~ Joe,
I recommend this one, Mundorff supreme 0.33uF/1000V.
You can buy it from local web store, Tube Fan Studio.
And the most important, Its price is not too high to buy four of them in once. And more...the quality of sound is very good!
-
Thanks, JimL!
I get your point and be appreciated your work of SRX+. -
17 minutes ago, spritzer said:
That's just the pins and they are easy to open up. Well a bit tedious when I had to do that to some 500 sockets...
You mean the tail screw is easy to loose, right？
Put some solder on it can fix the problem, only do that after you screw up tightly! -
1 hour ago, Blueman2 said:
Does anyone know a good source for female 5-pin pro-Stax connectors?
I recommend this ebay item. this teflon socket is very very... yes! very... tight！
http://www.ebay.com/itm/280935223236?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649&rmvSB=true -
Hi~ JimL & guys,
I've got question, maybe some fool one.
Why don't use CCS replaced the 250K resistor near the second 12AT7？
-
4 hours ago, sorenb said:
Your board seems filled with flux residue ... did you, or the skilled someone, clean the boards before use?
The soldering seems like it could be enhanced a bit also - might be the light and how the picture was taken ...
So.....What do you mean？
The fact was there is two time blowup of the PSU.
Did the layout cause the blowup in some unknown situation？
That is the issue we really care about. Am I clear for you？
-
About 3 weeks ago, Joe reported his PSU of KGST blowout twice. After discussion through FB, I suggested reconstructing the whole thing by a skillful someone. I recommend the man, Getpointlee, to take the job. Getpointlee, once a audio dealer and a owner of audio manufacturing, live in Taipei, Taiwan. You may be interested in his blog(http://getpointlee.blogspot.tw/) . Another local DIYer provided a new PSU board for this whole new reconstructing. There are about 3 to 4 Diyers in Taiwan concern the progress of the problem that Joe met. We constantly discussed on the local forum or on the FB through private message.
Unfortunately, It blowed up again!
First blow is the bias parts, then the positive rail patrs.
Very Very strange, right?
After detailed check, Getpointlee found the problem may caused by the arc between the TP and the negative output rail. as below picture~
The distance between the TP and the negative rail output line is just only 1mm, but the voltage between theses is almost 1000V！ One mm is enough or not, could be a issue to discuss. However, no one here would like to have third blow again. So, for the safety issue, Getpointlee recommend the mod as below~
Wish these information help your guys to know that the HV PSU blowup may cause by the arc between the TP and negative rail output.
-
Hi~ Joehpj,
I and my friend had noted your problem of KGST, and we found we should be in the same country Taiwan, right?
If you did need any local help, please feel free to let me know. There is a discussion on the local forum, AA. I think you should know it. We all be there!
Good luck! -
ksa1156 works fine as 2sa1486 replacement with the 270V zener and is a current part
Ask a question: KG point to use 270V zener while use ksa1156 to replace 2sa1486.
Where is the exact component that KG mean?
Would anyone like to provide photos to explain for me?
Or using this part of kgsshv psu schematics explain for me. I'm truly newbie indeed !
-
NO. you are missing the point.
The point is a fair bit MORE current.
one 10m90s is not going to handle that.
you would need 3.
and you need 3 x fqpf8n80c.
other than that, both supplies are about the same
in cost and performance
ksc5026 works fine as 2sc3675 or 2sc3840 replacement and is a current part
ksa1156 works fine as 2sa1486 replacement with the 270V zener and is a current part
Thanks KG！ I'll be back to the kgsshv psu while you give me the information of the fets replacement. Thanks!
-
I draw the schematics to show my modified version of the T2 psu for megatron below.
Dose the modified schematics work?
Any comments will be welcome. Thanks!
-
Dear all,
I've got an idea to using T2 psu in the megatron plan. Is it an good idea, or not?
It's nearly impossible to get 2SC3840 & 2SA1684 in local resource, and, fortunately, I got six 2SC3675！
So, I wonder to modify the T2 psu by adding more one fqp8n80c.....
Is it work fine for megatron ?
krell ksa5 klone
in Do It Yourself
Posted
Hi~ Guys,
I know this is late to be interested in doing KSA-5.
However, the Alexcp's modified version of KSA-5 inspired me to make one.
So, I wonder if you guys had the bare PCB of KSA-5 to offer?
I am glade to buy one, please PM me.
Sincerely,