F5 Turbo Builders Thread

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looks good:)
the link is there in case one wants to og balanced:)

Thanks AudioSan. But, it's ok that the Link was sent to the ground connection of the output board?

I didn't know it could go balance. I guess if both left and right channels were used in a stereo amp to make a mono balance amp?

BTW- after reading 6L6's Howto build a F5T v2, I decided not to build the v3. Seems that one gains very little by going to 100w, but looses a lot in turms of time and money.
All that for 3 db? Not sure I need it.

Thanks again,

Vin
 
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Joined 2010
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Thanks AudioSan. But, it's ok that the Link was sent to the ground connection of the output board?

I didn't know it could go balance. I guess if both left and right channels were used in a stereo amp to make a mono balance amp?

BTW- after reading 6L6's Howto build a F5T v2, I decided not to build the v3. Seems that one gains very little by going to 100w, but looses a lot in turms of time and money.
All that for 3 db? Not sure I need it.

Thanks again,

Vin

Vin

Just jumper to the ground pad next to the Link pad
 
here Is our F5T so far, need to mica and grease the Mosfets, wire everything up, understand what Im doing with the selector switch which i think Ive wired up wrong. the nice thing is its using cat 7 cable for all the phono/input connections in one shot.


Massive Vu Meters from the army I think! somehow ill need to calibrate them with the VU driver to give some idea of DB, any ideas ? my multimeter has a DB measurement.
P1050895.jpg


As you can see nothing is wired up yet, Ive added internal fuses for extra protection which ill have to find an appropriate value. 20x 10,000uf caps
I was a bit worried about the long legs on those resistors on PSU board as they carry +/- Volts. and was worried if they are a bit close to the B1 just below.
P1050994.JPG


Official Diyaudio Gain stage boards and output boards, little transistors are tied which i had seen another member here do.
P1050896.JPG


Both boards will have the common earth tied together, i think ill put a grounding point somewhere just above the boards so all earths go to one place. please let me know if anyone can see any issues lol
P1050955.JPG


The two caps there I didn't know if i should put them on the gain stage or on the OP boards. looks like either will do, and from what I understand they may not be needed at all.
The tiny 1nf caps I think are needed for Stability, realy
P1050990.JPG


Vishay Dale resistors, will be using Mica (split to ultra thin sheets) /grease
P1050986.JPG


Mounting Diodes on Stripboard and lining up holes, bit of a pain in the ****.
P1050981.JPG


This is my Messy Stripboard wiring, I could have used the Diyaudio power supply boards.
as you see Im using a whole bunch of strips as the ground points.
Its a bit messy but hopefully will be ok!
P1050919.JPG


The selector switch which I may have wired up wrong!, Cat 7 computer network cable with shielding
Pretty cool!
The top set of contacts switch and bottom seperately.
P1050907.JPG


VU driver board from ebay. the fact that chip has been filed so we don't know what it is is a bit worrying.
P1050947.JPG


heres more pics on my facebook page hopefully you can see the gallery,
i think its good to share all our pics so we can get ideas from each other!
 
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6L6

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What an impressive project!

I'm looking at the PSU and trying to understand why it won't completely go up in smoke when you first apply power... Can you draw out exactly all your connections?

Also, when you get your mechanical done (mounting of all the PCB and such) remove all the "not F5T bitz" and do the amp in stages - PSU, one channel at a time, B1, panel meters, etc...

If you try to hook it up all together, and then apply power in one go you are certain of letting out some magic smoke somewhere.

PM me when you get a chance.
 
Make sure you have the psu right before you do anything else. Something looks off. You should have 8 diodes for single PSU or 16 for dual mono if doing ti according to article. Looks like you only have single Graetz, wheras the article shows a dual Graetz setup.
 
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Make sure you have the psu right before you do anything else. Something looks off. You should have 8 diodes for single PSU or 16 for dual mono if doing ti according to article. Looks like you only have single Graetz, wheras the article shows a dual Graetz setup.

You can use a center tapped transformer and a single bridge for mono or stereo supply, but dual mono would have at least 2 bridges.
Somewhere I saw in the F5 thread someone used a center tap and single bridge supply. You can also tie two windings ends together and form a center tap, if you have the polarity correct.

But the 2 bridge supply for mono should be better, I think, less resistance to current flow.

Rush
 
What an impressive project!

I'm looking at the PSU and trying to understand why it won't completely go up in smoke when you first apply power... Can you draw out exactly all your connections?

Also, when you get your mechanical done (mounting of all the PCB and such) remove all the "not F5T bitz" and do the amp in stages - PSU, one channel at a time, B1, panel meters, etc...

If you try to hook it up all together, and then apply power in one go you are certain of letting out some magic smoke somewhere.

PM me when you get a chance.

as far as I can see this is wired exactly as it shows in the F5 Turbo PDF manual, One of my boards handles the Neg the other the positive supply, and i shall join the two very soon.

In that manual the power supply is shows has 4x Diodes. ? and being me I presume that schematic on the V2 section is for two channels!

Yes I plan to put together In stages :) I will try to draw out over the stripboards the connections, thanks!
 
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6L6

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Joined 2010
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as far as I can see this is wired exactly as it shows in the F5 Turbo PDF manual, One of my boards handles the Neg the other the positive supply, and i shall join the two very soon.

The diode cases must be insulated from the chassis, as do the mosfets (which you mention)

What kind of transformer do you have? Specifically, what is the secondary wiring?

I'm still not enthusiastic about applying power to your PSU.

In that manual the power supply is shows has 4x Diodes. ? and being me I presume that schematic on the V2 section is for two channels!
What schematic, the PSU? Yes, it will power 2 channels of V2. (Or one monoblock V3.)

The diodes are shown is 2 in the schematic because the MUR devices are 2 diodes in parallel.

I would much rather see a pair of 200V 35A monolithic bridges used in the configuration of a normal F5, but with the big cap bank that you have.
 
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The diode cases must be insulated from the chassis, as do the mosfets (which you mention)

What kind of transformer do you have? Specifically, what is the secondary wiring?

I'm still not enthusiastic about applying power to your PSU.



What schematic, the PSU? Yes, it will power 2 channels of V2. (Or one monoblock V3.

The diodes are shown is 2 in the schematic because the MUR devices are 2 diosed in parallel.

I would much rather see a pair of 200V 35A monolithic bridges used in the configuration of a normal F5, but with the big cap bank that you have.


This is the schematic from the F5T article, see below.
It is a center tapped transformer.

Rush
 

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  • F5T Power supply.jpg
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The diode cases must be insulated from the chassis, as do the mosfets (which you mention)

What kind of transformer do you have? Specifically, what is the secondary wiring?

I'm still not enthusiastic about applying power to your PSU.



What schematic, the PSU? Yes, it will power 2 channels of V2. (Or one monoblock V3.

The diodes are shown is 2 in the schematic because the MUR devices are 2 diosed in parallel.

I would much rather see a pair of 200V 35A monolithic bridges used in the configuration of a normal F5, but with the big cap bank that you have.

center tapped 600va transformer same as in F5Turbo manual where he says "a beefier power supply" , Where it says D1 to D4 I presume that means 4 actual Diodes.
Each Stripboard is acting as one half of The PSU.

Also you can see on my boards ive drawn The Diodes polarity in black pen, Im sure it will be ok If its not you can have a laugh when it goes bang! haha

But yes I could scrap those diodes altogether and go for 2x bridges as I have some left from an old Zen V4 which are 200v 35A.

Whats the advantage over the MUR's ?

Transformer says 130306, bear in mind on my photo Ive not made the connections from one board to the other Yet.