• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

EL84 Amp - Baby Huey

Electrically both are OK.
The original STU9HN65M2 is an I-PAK (TO-251-3) device.
The 2 you have listed are TO-220 which have wider pin spacing (round figures 2.9mm for the TO-220 rather than 2.3mm for the I-PAK). You would have to squeeze the pins together a bit but the actually pinout is the same.

I would prefer the first (Vishay) which is all plastic case so no hot (voltage and temperature) tab.

A minor application of the good old "brute force and ignorance" can make them fit and once fitted they will work.

BUT
Aussie Element14 lists the original STU9HN65M2:
http://au.element14.com/stmicroelectronics/stu9n65m2/mosfet-n-channel-650v-5a-to-251/dp/2460393

Check Element14 Part Number 2460393 on the Malaysia site. That would be best.

Cheers,
Ian
 
Hi potepuh,

Yes, you can put a bigger capacitor, but it will not fit on the PCB !

Hi Ian,

Nice to see you back on your thread :) I have waited the end of the third GB before to introduce the KT120 quad to avoid too much confusion about different amplifiers and I will now start a new thread for this last one. By the way did you receive my mail with the last schematic ?

Best regards,

Marc
 
Hello Potepuh:
I have just recently finished the build of my version of this amp. (pictures soon, should we start a bby huey build thread?).

I highly recommend you go with higher voltage capacitors. If you want to try a range of tubes you will need your voltage to go upto 500v or so. The capacitors on the BOM I used are 450v, Upgrade to the 600 or 650v ones. It will give output tube rolling options, which is pretty great. I am using 6P6S(6П6С, 6v6) and am about to try 6l6gc, and if I can get my filament amperage up I would like to try kt66, and EL34/6ca7 as well.
Marc put up a chart a while back that compares the various tubes in the family.

View attachment Comparaison pentodes et tetrodes.pdf

Seems to me 500v gets you into the range pretty good.

I hope this helps
 
Hi Scott,

I will follow your suggestion and prepare a new thread for building the EL34 Baby Huey soon, since there are already 330 PCB's sold and 20 more in waiting list for a 4th GB :D

Your suggestion to use 500 V capacitor is very good, but builders should not use higher voltage with this PCB because there could be some isolation problem :mad:

In the mean time my EL34 Baby Huey is almost finished (see picture). All this mechanical work is made by Philippe who is much better than me for this task :) I was lucky to meet him and that he is also living near Bandol in the South of France because before in the past most of my electronic design didn't have a case, now they look professional :cool:

Best regards,
Marc
 

Attachments

  • EL34 Baby Huey nearly finished.jpg
    EL34 Baby Huey nearly finished.jpg
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New thread for building the EL34 Baby Huey

Hi everybody,

As SCD suggested and because the EL34 Baby Huey interest is still growing, I have started a new thread on the building of tubes amplifiers based on this PCB at this address : http://www.diyaudio.com/forums/tubes-valves/326920-el34-baby-huey-amplifier.html#post5534012 :)

I will regularly add information but you are also welcome to show pictures of your amplifiers and to discuss the choice of tubes or others components...

Thanks for your strong interest in this small project ;)

Cheers,
Marc
 
Hi sunil,

No sorry I didn't have any spare, it was my first Baby Huey PCB and I made only 5 pieces, all gone :mad: I know that you want to use your ECL86 tubes, but otherwise you can still buy two of the last 6 EL34 Baby Huey PCB available in the last GB made by prasi...

If you want to make the ECL86 PCB yourself, I can send the Gerber files, give me your email by PM...

Hi polycell,

Any red LED will be OK, the forward voltage should be around 1.7 V and the current will be very low, few mA.

Marc
 
Marc,

Thanks for the info. I didn't think about asking for the gerber files to get some PCB's made. In the end I used your schematic and layout screenshots to create my own PCB's using Kicad but with the major difference in that the heaters are wired for series (using PCL86). I also made the PCB 100x100mm to allow a bit more space for the components. All that's left is to get them made at one of the ridiculously cheap China PCB manufactures.

Polycell
 
ECL86 / PCL86 PCB

Hi,

Following new growing interest in the smallest Baby Huey, I have enclosed the Gerber files and updated schema for those who are interested to build it :D

Best regards,
Marc
 

Attachments

  • ecl86 amplifier 5.zip
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  • Schema ECL86 Oct 2, 2018.pdf
    136.4 KB · Views: 279
  • PCB ECL86 Oct 2, 2018.png
    PCB ECL86 Oct 2, 2018.png
    80.5 KB · Views: 720