Well Mr minek123 suggestion is excellent. TTC004B is very good substitute for 2n3019 but in case you donot get this transister you may go for KSC3503 which is still under production by ON Semiconductor.
TTC004B is much robust transistor than KSC3503 but in our circuit collector current of VAS is max 15ma.
KSC3503 is a Video Transistor and its performance is excellent. I have tested this in my prototype BJT Circlophone with 2N3055/ 2N3773 output transistors. Picture of Genuine KSC3503 attached.
Attachments
If you use KSC3503 or KSC3505 as VAS transistors, it was recommended to add 4.7pF caps between Base and Collector.
See https://www.diyaudio.com/community/threads/my-little-cheap-circlophone-c.189599/post-2971394
See https://www.diyaudio.com/community/threads/my-little-cheap-circlophone-c.189599/post-2971394
Welcome to Elvee's Circlophone thread. Congratulations for nice and beautiful build. Please share technical performance parameters and the passive Tone Control circuit for the benefit of boarders. It seem you have used 2N3019 in VAS.
The build looks professional in build quality.
Please share your experience of audio quality.
I'm glad you like it. I used 2n2219 as there is no 2n3019. However, they get very hot. I bought the passive tone control board on ebay years ago. Prepaid card. I like the sound quality very much, but the sound gain seems a little low. It may be caused by the tone control circuit. I just finished the circuit. I will write more detailed information in the future.
Have you used 2N2219 or 2N2219A? Vceo of 2N2219A is only 75V and that of 2N2219 is only 60V. This transistor is exposed to full rail voltage in the schematic and in your case 25V+25V=50V which is very high in your case. Vceo of 2N3019 is 80V. I think this transistor is not suitable for the present schematic and may lead to possible failure. You have to use ring heat sinks for this transistor.
It will be better if you request Mr Elvee for his comments on this issue.
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Congratulations for the, yes you can say full amplifier combo, looks very good ! Really very good (super) !
Also thanks for using the PCB layouts I provided.
Yes, the transistors 2N3019 are hard to get, I would have had to make a small change in my layout so that you could also use other transistors Q5,Q6 e.g. in the TO 126 housing. I use 2SC2690.
Thanks Oscar
Also thanks for using the PCB layouts I provided.
Yes, the transistors 2N3019 are hard to get, I would have had to make a small change in my layout so that you could also use other transistors Q5,Q6 e.g. in the TO 126 housing. I use 2SC2690.
Thanks Oscar
Good For you - NanoFarad # BhowmickAlthough currently i'm enjoying my lm3886 build but no one stopping me to find exotic parts for my Circlo!Sanyo C3417.
(The truth is i don't want to break my Sanyo A1209-C2911 pairs)
View attachment 1071340
I think you have serious superiority complex! Please don't use the term addressing me, i don't like it. thank you.
i have no complex................. i think you have after seeing some replies you have given on this forum. and it was not a very decent way to say something to some one who may not know a lot of things.
Hello, it is defensively time for me as well to join the Circlophone community, planing the build with start of getting all components.
Well what to say, this thread is massive
including builders thread. anyhow, tried to find some more comprehensive BOM, but all parts are described loosely thru all the posts. So I have tried to do one myself, purchase from Mouser. I'm a fan of open software so the file is Open office, not everybody like to open this kind of files (virus and stuff) so attached PDF as well. With that said, BOM is a BJT version. if someone has any comments i will add or remove. Next to do is trying to fix the PCB in KiCad and use FlatCam for my CNC Router. / Brgds
Well what to say, this thread is massive
including builders thread. anyhow, tried to find some more comprehensive BOM, but all parts are described loosely thru all the posts. So I have tried to do one myself, purchase from Mouser. I'm a fan of open software so the file is Open office, not everybody like to open this kind of files (virus and stuff) so attached PDF as well. With that said, BOM is a BJT version. if someone has any comments i will add or remove. Next to do is trying to fix the PCB in KiCad and use FlatCam for my CNC Router. / Brgds