All things Green Pre

[enthalpystudios]

Thanks guys... forgot the jumper wire on the PSU, but threw it in and i'm getting about 48.1 on the phantom, 16.16/.5/-17 on the others. Seems to me this is around where I want things.... I'll give it a go tomorrow with a channel if noone thinks those voltages are problematic for any reason.

Just need the toggles.... speaking of the toggles, are they all on-on, on-off, or a combo of both? I think I can get a good price with a trip up to my local surplus joint.

Thanks,

billy

 

[HappyTom]

[quote author="enthalpystudios"]Thanks guys... forgot the jumper wire on the PSU, but threw it in and i'm getting about 48.1 on the phantom, 16.16/.5/-17 on the others. Seems to me this is around where I want things.... I'll give it a go tomorrow with a channel if noone thinks those voltages are problematic for any reason.

Just need the toggles.... speaking of the toggles, are they all on-on, on-off, or a combo of both? I think I can get a good price with a trip up to my local surplus joint.

Thanks,

billy[/quote]

Phantom is on/off spdt
HPF is on/on spdt
Phase is on/on dpdt

I used on/on toggles for both phantom and hpf.

HT

 

[peterc]

the output pot,when ccw should stop the sound,but it doesn`t.there`s some sound and a litlle distorted.when fully cw,there`s more sound,and not distorted

Check that the Gnd leg of the pot is FIRMLY connected to GND

Peter

 

[peterc]

16.16/.5/-17

Check that grounding, the .5 is too high. Where are you placing the common lead of the meter?

Peter

 

[enthalpystudios]

Placing it on the 0v of the secondary(s).

Also tried it on the neutral coming out of the wall. Should it be tied to the wall ground (third prong)?

Also, the wiring in this place is horrendous. I've been meaning to dig into it.

Thanks for the heads up, I thought that seemed a little high, but as it's the first time I've measured my ground, I have no frame of reference whatsoever.

Grounding. Oh man oh man. I get it.... but doing it properly, there's the intense part.

How close to 0 should one be able to get it?

 

[peterc]

Use the Gnd from the DC side of the PSU for your measurements & then check voltages.

Peter

 

[louder]

alo peter
what do you mean by the ground leg of the pot firmly connected to ground?.
sorry for the stupid question.
best regards
pedro

 

[Freq Band]

from my post/reply one or two pages back....

re: BC550/560 cross reference....
NTE recommended their NTE159 and NTE123AP as substitutions, and sells them in a "matched complementary pair" (+-10%) as well.

Some specs:

http://www.nteinc.com/specs/100to199/pdf/nte123ap.pdf
http://www.nteinc.com/specs/100to199/pdf/nte159.pdf

If someone could check that these would work..........I'll wash your car. :razz:

=FB=

 

[peterc]

Quite often, if a pot is turned to the off position, & signal is passing through it, the problem has something to do with a faulty Gnd connection.

Peter

 

[enthalpystudios]

Question about the caps... Can I use ceramics for the pf values? Or does anyone know where I might find polycarb/propylene/styrene/polyester 22 and 150 pf caps in the US???

 

[clintrubber]

[quote author="enthalpystudios"]Question about the caps... Can I use ceramics for the pf values? Or does anyone know where I might find polycarb/propylene/styrene/polyester 22 and 150 pf caps in the US???[/quote]

Ceramic NP0/CG0 are fine !

(See for instance http://www.johnhardyco.com/pdf/990.pdf on page 8)

 

[John Hardy]

Ceramic NP0/CG0 are fine !

Actually that is "COG", not "CGO", not to be confused with a fast car from the 1960s known as the "GTO".

John Hardy

 

[clintrubber]

[quote author="John Hardy"]

Ceramic NP0/CG0 are fine !

Actually that is "COG", not "CGO", [/quote]

Oops, I goofed...

Now we're talking about this let's set it straight for once & all:
is that O/0 in COG actually a zero or the 15th letter ?

And the '0' in NP0 is a zero, right ? (so NPO needs to be NP0 then one would say, as it stands for Negative-Positive-Zero)

not to be confused with a fast car from the 1960s known as the "GTO".

John Hardy

BTO you said ? Yes, I've al their records :wink:

Regards,

Peter

 

[Freq Band]

When searching for Green Pre (or other) info, I find it much easier to use Google, instead of the forum "search".
Google allows you better direct accsess to specific words or phrases....than the forum (php, phpbb2) search.

The best example: the "forum" search will find the word you entered.....but only directs you to the first page of the thread.....just try to find that among 150+ posts....it might be on page 2, or page 22... :?
In google (or others), the results take you straight to the correct page, and highlight each word/phrase.
You may already know this, but type it in Google like this, if you are searching for the word....say... coffee........

+coffee site:www.groupdiy.com

to find a phrase, plus two seperate words :

+coffee +spilled +"large fire" site:www.groupdiy.com


A plus before the word is not necessary, but it instructs google that it must be included in the results......and a " - " before a word or phrase means must not be included. Tip: for some reason google finds the smiley "Mr.Green", which was frustrating for me until I added -Mr.....thereby eliminating all Mr. Greens.


(now I have no excuse for asking a repeat Q.....damm :?)

=FB=

 

[Freq Band]

Or does anyone know where I might find polycarb/propylene/styrene/polyester 22 and 150 pf caps in the US???

I got some 22pf pstyrene at
http://www.allelectronics.com/index.html
...but it's not in their catalog. They're in their retail bins. You could try calling.

=FB=

 

[John Hardy]

Now we're talking about this let's set it straight for once & all:
is that O/0 in COG actually a zero or the 15th letter ?

I don't know!

And the '0' in NP0 is a zero, right ? (so NPO needs to be NP0 then one would say, as it stands for Negative-Positive-Zero)

That is correct. You can see my paper about COG and NP0 caps on page 8 of my 990 data package:

http://www.johnhardyco.com/pdf/990.pdf

To quote from that paper: "NP0 = Negative-Positive-Zero, indicating a temperature coefficient of capacitance that is neither plus nor minus, but is very close to zero. Tempco = ±30ppm, -55 to +125°C."

Thank you.

John Hardy
The John Hardy Co.
www.johnhardyco.com

 

[Kev]

Hey John !!
good to see you quoting yourself
err
and good to see you haven't forgotten us.

 

[HappyTom]

[quote author="Freq Band"]When searching for Green Pre (or other) info, I find it much easier to use Google, instead of the forum "search".
Google allows you better direct accsess to specific words or phrases....than the forum (php, phpbb2) search.

The best example: the "forum" search will find the word you entered.....but only directs you to the first page of the thread.....just try to find that among 150+ posts....it might be on page 2, or page 22... :?
In google (or others), the results take you straight to the correct page, and highlight each word/phrase.
You may already know this, but type it in Google like this, if you are searching for the word....say... coffee........

+coffee site:www.groupdiy.com

to find a phrase, plus two seperate words :

+coffee +spilled +"large fire" site:www.groupdiy.com


A plus before the word is not necessary, but it instructs google that it must be included in the results......and a " - " before a word or phrase means must not be included. Tip: for some reason google finds the smiley "Mr.Green", which was frustrating for me until I added -Mr.....thereby eliminating all Mr. Greens.


(now I have no excuse for asking a repeat Q.....damm :?)

=FB=[/quote]

Thats because you search for topics. "Display results as: Topics"
If you search for posts instead you'll only get the posts that match.
Hit the checkbox "Posts" and you're fine.

HT

 

[Freq Band]

I see my error, thanks. I'll use both ways now.

F.Y.I. any newbies ordering caps might find this capacitor converter helpfull. (keep in mind uF = microfarads):

http://www.onlineconversion.com/electric_capacitance.htm

=FB=

 

[Freq Band]

Almost done !!
I still need to drill some holes in the case, and paint a faceplate.
---------------------
One capacitor value is yet to be soldered, because:

I already used some quality .1uf (100nf) polys 50v (STK brand) everywhere except the meter section and next to the center NE5532 (would not fit). I also ordered some ELNA Cerafine lytics from Welborne.
The problem is space. The two Cerafine 22uf lytics 63v (smallest they had), will not fit between those .1u STK's......
....so my question is this: Which should be of "better" quality? --those two 22uf's --or the two flanking .1uf poly's ?
I can replace the .1uf with smaller ones of less "quality" and put the 22uf Cerafine's in.....or keep the good .1uf's, and put in cheaper 22uf's.

advice??

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