- #37 [kit271], 19-05-27 16:376FQ7 是否= 6CG7
- #36 [thomasc2], 19-05-26 12:54臨淵羨魚不如退而結網,要認識/計算一個簡單膽機線路所需的電子知識其實不多,現今網上資訊亦相當充足,有心學絕唔難.
Google search "EL156" 就可找到大大堆線路,當然並不是擺得上網就一定work,是好是壞又需要一定的知識去判斷. - #35 [kit271], 19-05-26 09:55
-
- #34 [kit271], 19-05-26 09:52這個是UL接法,又有埋電壓讀數參考,正,谢cat 師兄
- #33 [CodyChan], 19-05-26 09:42請問有單端線路圖提供嗎?
再次謝謝各位關注。 - #32 [cat2013], 19-05-25 23:47後補
- #31 [cat2013], 19-05-25 23:36#25
參考下啦 - #30 [kit271], 19-05-25 18:46Re#27
師兄的文章小弟重覆看了三四次,很值得DIYer參考,正! - #29 [bambino], 19-05-25 17:19懂一些電子知識會玩得更有樂趣, 又更安全。
最後修改時間: 2019-05-25 17:19:52 - #28 [i-walker], 19-05-25 16:31很羨慕懂得電子技術的 c-hing, 玩膽機都玩得更專業、更開心!^^
- #27 [thomasc2], 19-05-25 10:57轉眼又十年. 原文原本是放在yahoo bloc,後唔為意yahoo bloc摺左,結果幾編diy記錄都冇曬,感謝師兄將個post挖番出來,現在是不會再這樣長編大論了.
- #26 [benchocl], 19-05-25 07:28各位C兄早晨,小弟請教各位師傅,我手上有 FL152 和 WE2C51 各位有電路圖嗎?和砌機嗎?
- #25 [kit271], 19-05-23 08:41近排都想砌一部PP pentode/UL, 想用6h30推KT150或 EL156, 有無好介召?
- #24 [CodyChan], 19-05-22 22:47請問有沒有師兄可以提供 6SN7推EL156 or 12AX7推EL156 的線路圖給小弟參考呢?
萬分感激. - #23 [thomasc2], 09-09-22 10:53cmc168 hing
Actually the plate chokes were for the driver tubes in the amp I mentioned. The output stage was not parafeed. Dr. King has kindly lent me another pair of plate choke recently. I will work on them shortly and put more details about that amp here. - #22 [cmc168], 09-09-21 17:37Hi thomas,
yes,measured at sec of tx.
i use poshan 40H anode choke,u said HF roll off may be due to roll-off in your driver stage,what tube u used?i perfer driver tube with low Ra that improve hf response more.
also what kind of parafeed tx u used at the time?
the poshan opt i used was a giant size with 50w power rating,so LF response ok.
I shall inform u once i got time to complete the el156 with new circuit . - #21 [thomasc2], 09-09-21 11:44cmc168 hing,
Thanks for sharing your experience.
70KHz -0db is amazing. So, that was measured at the output end of the opt? I did an anode choked amp some time ago and got very sharp HF roll off making the amp not listenable. Obviously it was due to the high inductance/capacitance of the choke I got. Could the undesirable LH response of your parafeed 300B caused by insufficient inductance of the choke?
My EL156 sounds dull but you said yours
sounded clinical. I found my po shan opt weak in LH but you found yours poor in HF. Would really wish to know more about (and if possible to hear) your EL156 amp when it comes too light again especially if parafeed, ccs... can do any magic on it. - #20 [cmc168], 09-09-20 23:32Thomas hing,
thankyou for your explanation.
the el156 amp was just my experiment quite some time ago,i have not made comparasion with other cct configuration at that time nor i have vivid impression with it.I have no idea whatsoever whether stc is good or not.
At that time,i use 6c45 (i very much appreciate the robust construction of this single triode tube with high anode dissipation,ultra low Ra)to drive chinese el156 with a stc and use poshan opt.
Later on,i test the poshan opt on scope(with dc current passing to sim the actualworking condition) and found it unacceptable due to HF roll-off starting 9000hz!
Then i put aside the amp project,Over the recent year,i switched to dirve 300b with different tubes like 6c45 and 12gn7 and this time i use parafeed o/p stage,use anode choke and a toroidal power trans (to test the performance of this tx to investigate the possibility of replacing expensive opt).
I am quite satisfied with the HF response which easily reached 70khz -0db and 100khz-3db.However the LF still has room to improve and i am working on that.
If time permit shortly i shall hook on el156 again with parafeed config and this time will try some new issues such as the use of constant current source in driver and output stage and direct coupling. - #19 [thomasc2], 09-09-19 10:50cmc168,
The circuit you posted was originally designed by a hi-hand called Chris Chang in Taiwan very long time ago. The most interesting part of the circuit is that V+ is added directly to the cathode of the EL156 in order to raise the potential to implement the direct coupling of the 5842. When he first published his circuit (at DZ ??? At that time, DZ was really a super good place for diyer), I had also talked to him about the high Vg2 in his circuit. His explanation was that as long as the total anode + G2 power dissipation was within the spec, there should be no harm for the Vg2 exceeding its designed maximum. I doubted. Since Chris purblishing his circuit, he had never talked about it any more. I wonder he or some other people has successfully done it. During the same time, I read some other posts on some foreign forums and found one saying that actually the EL156 is rather fragile and he strongly advised people not to raise the Vg2 above its spec as it could really burn the tube. I'd rather trust this guy.
In fact, I myself have some sad experience with EL156. In my past 10+ years of playing on tubes, I could remember that I have burnt only one tube due to my misusage. It was a EL156! I forgot to connect a load to the amp when I tested the amp. Some loose part of the amp created some noise and the tube was burnt, just that easily!
I have never tried STC before. Would it be possible for you to talk about a bit more about your amp? - #18 [cmc168], 09-09-19 01:31~The biggest problem with EL156 is, IMHO, is its low Vg2 toleration, 300V only~
Seems ok wor...i found this triod connection cct on the net.
http://essues.com/Chinese/Schem/EL156SE/EL156SE.htm
Also,i built 6c45 push el156 before,using super triode connection (Vsg > Va) ,Va use 500V,no problem and sounds not bad.(a bit clinical sound imo) - 下一頁 (2 of 3)
- 返回 ...