find picture of any First Watt amp without top lid , and observe details
do you really need better tutorial?
do you really need better tutorial?
I'm having a real hard time understanding the question after re-reading it 5 times.
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Thank you for your reply, sorry for the wrong translation I use google .... Yes I know it twisted but I just wanted to know the interest of doing it? If we do not do that it changes a few things?
If you are curious what happen just try not twisted them in your M2.
Some cross talk noise interferances ? Me think frenchglish 😀
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Here is how I made, the photos is in attachments .... The amp works perfectly , thank you for your response Soundhappy
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Ok if work perfectly so don't need any changes.
Maybe 0.47R 5 Watts output source resistors upgrade to Mills or MPC74 but is not urgency.
Congratulations Uchu007 great quality diy work !
Enjoy
Thanks, the output resistances are mundorf MR5 0.47 ohms .... I increase the capacitors has 312000 uf and I confess that I am surprised by the quality of this amp, I think it takes a preamp now because My dac and may be a weak one ....
I re-purposed my F5 using M2 boards from Tea-Bag. They are in a 5U chassis which is a bit overkill, but the upside is no hum due to the auto-former being quite a distance from the mains transformer.
Getting the offset to null was fun...not. My offset was negative so I ended up pulling the boards and soldering sockets in place of R7. Then searching through resistors I had on hand ending up with 47.5k and 220R in series measuring 47.72k. This gave me enough adjustment with P1=5k, and R6 remaining at 47k. Then I just soldered the resistors into the sockets. It sounds simple, but it was a lot of trial and error.
Here are the pics to prove it really happened:
Getting the offset to null was fun...not. My offset was negative so I ended up pulling the boards and soldering sockets in place of R7. Then searching through resistors I had on hand ending up with 47.5k and 220R in series measuring 47.72k. This gave me enough adjustment with P1=5k, and R6 remaining at 47k. Then I just soldered the resistors into the sockets. It sounds simple, but it was a lot of trial and error.
Here are the pics to prove it really happened:
MPC74 are non inductive , non magnetic :
Resistance a couche metallique Fukushima Futaba MPC74 5 W 0,47 ohm 5% 0.47 Ω sortie radiale MPC74 5 W 5 % 1 pc(s) sur le site Internet Conrad | 443893
It's superb to try if compare with high price Hi-Fi boutique resistors , metal oxide and ordinary metal films.
I do myself experiments and is my keeper source 0.47R.
Have fun 😀
Yeah I know, that would have been easier as it turns out. I didn't have a 10k trimmer so I committed to changing R7. Took me a little while, but it's all good.
I see you guys talking about the source resisters. I just used the standard Panasonic ones I had lying around. Do you recommend changing these out?
As a side note, I'm getting a loud pop when shutting the turntable motor off. It's always made a pop but now it's very loud...in fact it scares me a bit. The only thing I remember changing is the amplifier. I could switch back to the F4 to see if it makes a difference but it's out on loan to my brother. Does this make any sense? Any thoughts?
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Relax not urgency 😀
Can be funny to compare sound if you solder two of them but only on the one mono side of yours M2 channels.
Strong parameter of Futaba source resistors are internal construction structure and materials.
Ordinary metal resistors or metal oxide are spiral looped...and is total of 5 elements not 3.
Only MPC74 (5 watts) and MPC78 ( 2 watts) are non magnetic versions.
" Bulk z-foils " on the budget hahaha.
BTW new Mr. Pass amplifiers are source resistors free !
Example : DEF
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You can see inside spiral and film grains in glass vacuum loaded resistor.
Instaled sockets for Toshiba and LSK jfet's roll & bench M2 experiments.
Stopped drinks beer's so get few more bucks i spend with pleasure on fancy components
Instaled sockets for Toshiba and LSK jfet's roll & bench M2 experiments.
Stopped drinks beer's so get few more bucks i spend with pleasure on fancy components
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Your loud pop is if you shutting all tuntable power off
or is if your turntable stops for pause or vinyl change ?
Greetings