Stock 68 spec W/2"OT and such...

[axeman]

Great looking amp strat78. Unfortunately I can't listen to the clips ight now.

I was just wondering if someone could fill me in on those diods in the rectifier. Are they just big freds or are they not fast recovery diods? What is the code on those?

Thanks

1n4008

[vh junkie]

Those are probably the 1N5408s, 1000v, 3A

vanhalen5150:
I sent you four of those, as well as four of the UF5408 (FRED) versions.

According to Dave F:
Use the 1N5408s for the bridge, and a smaller UF4007 (FRED) for the bias.

[vanhalen5150]

Those are probably the 1N5408s, 1000v, 3A

vanhalen5150:
I sent you four of those, as well as four of the UF5408 (FRED) versions.

According to Dave F:
Use the 1N5408s for the bridge, and a smaller UF4007 (FRED) for the bias.

Yup, they're waiting on my bench!

[rockstah]

Those are probably the 1N5408s, 1000v, 3A

vanhalen5150:
I sent you four of those, as well as four of the UF5408 (FRED) versions.

According to Dave F:
Use the 1N5408s for the bridge, and a smaller UF4007 (FRED) for the bias.

which ones? 1N5408 = http://www.mouser.com/Semiconductors/Di ... 08&FS=True" onclick="window.open(this.href);return false;

UF4007 = http://www.mouser.com/Search/Refine.aspx?Keyword=UF4007" onclick="window.open(this.href);return false;

the big ones look like the same Mohave uses which to me are real smooth sounding.

Mark

[vh junkie]

These are just bigger 3A versions, still just a regular diode:
625-1N5408-E3/73

FRED version:
625-UF5408-E3/73


FRED version of the bias diode:
625-UF4007-E3/73

[rockstah]

okay so why not these then - http://www.mouser.com/ProductDetail/Fai ... BXMh7sQ%3d" onclick="window.open(this.href);return false;

differnces?

FRED version:
625-UF4007-E3/73


FRED version of the bias diode:
625-UF4007-E3/73

[vh junkie]

okay so why not these then - http://www.mouser.com/ProductDetail/Fai ... BXMh7sQ%3d" onclick="window.open(this.href);return false;

Looks like the same thing to me.

differnces?

FRED version:
625-UF4007-E3/73


FRED version of the bias diode:
625-UF4007-E3/73

I corrected the text in my OP

[axeman]

Those are probably the 1N5408s, 1000v, 3A

vanhalen5150:
I sent you four of those, as well as four of the UF5408 (FRED) versions.

According to Dave F:
Use the 1N5408s for the bridge, and a smaller UF4007 (FRED) for the bias.

That's what I meant. Thanks. 1N5408

[vh junkie]

The bigger diodes in the bridge accomplish two things:
1) They look cool! Be sure to wrap the two vertical ones around the outside of the posts; and the crossing ones down the center of the posts for best looks.
2) When really bad things happen in the amp, the larger 3A diodes are less likely to fail and complicate the issue.

If you want to try the FRED sound, you don't have to replace all four diodes... you can do it by temprarily inserting a FRED between the point of the bridge and the red wire(B+)... the same place you would put the (100k) resistor if your were forming the filter caps... put the stripe on the inserted FRED towards the red wire...

[vanhalen5150]

What's the FRED sound?

[vh junkie]

Search for rgalpin and FRED...

[rockstah]

Strat78 - what do you think? http://soundclick.com/share.cfm?id=10395184" onclick="window.open(this.href);return false;

8ohm/50k feedback resistor

[Strat78]

Strat78 - what do you think? http://soundclick.com/share.cfm?id=10395184" onclick="window.open(this.href);return false;

8ohm/50k feedback resistor

Does this give the same results as 4ohm/100k? I like the crackle of that ATBL riff. I like the fullness of the 6ca7's especially in the mid section of the neck but the low strings are losing some bite. Your 69 with the el34's is sweet as honey but lacks that muscle and strain that the 78 has. Where did you have the volume and bass set on the 78? Is that a 2.5k in v1b? Is there a another cap in parallel with the .68/820 on v2A? Sorry, I've been flooded out of my basement so the cleanup has been taking me away from the guitar these days.

Forming Caps individually:
By ValveStorm
Isolating the caps:.
1) Start by removing the lifting one end of each of the two 2watt resistors shown in the picture, and removing the HT fuse.
2) Now you are only forming the mains.
3) Replace the fuse, now you are forming the mains and the screens.
4) Re-add the leftmost 2watt resistor, and you are forming the mains, the screens and the PI cap.
5) Re-add the other 2watt resistor, and you are forming (everything) the mains, the screens and the PI cap, and the preamp cap.
Be sure to drain the caps individually because with the resistors lifted, you can not drain the mains and screens from V1.

[rockstah]

Strat78 - what do you think? http://soundclick.com/share.cfm?id=10395184" onclick="window.open(this.href);return false;

8ohm/50k feedback resistor

Does this give the same results as 4ohm/100k? I like the crackle of that ATBL riff. I like the fullness of the 6ca7's especially in the mid section of the neck but the low strings are losing some bite. Your 69 with the el34's is sweet as honey but lacks that muscle and strain that the 78 has. Where did you have the volume and bass set on the 78? Is that a 2.5k in v1b? Is there a another cap in parallel with the .68/820 on v2A? Sorry, I've been flooded out of my basement so the cleanup has been taking me away from the guitar these days.

i hear. its a good question if there are the same. some years ago i remember the discussion of where you would assume that they are the same they actually aren't. seems like they would be but i don't recall.
v1b has 820ohm. just a lone.68u on v2a.
get back to guitar soon.
Mark

[vh junkie]

8 ohm / 50k is a good amount of NFB, keeps the amp tight
4 ohm / 100k is a less NFB, much looser
4 ohm / 100k would be about the same as 8 ohm / 135k