Gallien-Krueger 700RB

[MarkusBass]

I have a problem with G-K 700RB. It has several problems (possibly related to each other). First, there is a strong thump when the amp is turned on (after 5 seconds when it is unmuted). I found out that this is quite a new version for which I don't have any schematic. The input stage uses two separate transistors (previously it was one double transistor) and several resistors were changed, or removed (never existed in this version of the amp). Trying to measure voltages on emitters of the input stage causes oscillations of the amp.
The second problem is that there is -0.7V voltage on the speaker. But I don't see any shorted transistor (output or driver). It seems that the problem is related to the input stage because the voltages are incorrect starting from the input stage. And the output stage just repeats the voltages.

Mark

[T9c]

Here's the schematics

[MarkusBass]

Can you post the schematics once again? I cannot download them - they are displayed as "clear.gif" file. It looks like another attack against the forum.

Mark

[DrGonz78]

Hey I have the schematic and the power "off" thump service bulletin. Now it sounded like you have a power "on" thump but maybe it will be useful...

KRUEGER700RB.pdf

Gallien Krueger 700RB, 1001RB Turn-Off Thump Modification.pdf

[MarkusBass]

Thanks DrGonz78 but I need much never version. The one that I have has PC board version 0250-A5. The one that you posted is 0104-F. There are big differences between the versions, especially in the input stage and in the muting circuit.

Mark

[Enzo]

I have Adobe Reader X. The file for your 700RB series II is too large to post here. I can't seem to figure out how to snapshot one page and turn it into a stand alone pdf. Any help.


Otherwise call GK and ask for the 700RB-II files. Your is page 25 of 26.

[DrGonz78]

Oh I got that one too... Here is all broken down in 3 chunks. I guess this might not be the one either but here it is for others too. If you look at the 3rd attachment it only shows up to 0250-A4, this may not work for you.

gallien-krueger_700rb-ii_schPart1.pdf

gallien-krueger_700rb-ii_schPart2.pdf

gallien-krueger_700rb-ii_schPart3.pdf

Edit: Hey Enzo try downloading CutePDF Pro (Evaluation version) and open the file there... Then click on (Tools) and look about half way down the drop down menu. Select Delete Pages. Delete the pages you don't need, and save it as a new file name. Open that new file in adobe and save it again. Before saving in Adobe make sure to click the (Edit) drop menu and look at the very bottom to select "Preferences." Look at "Categories" and click on "Internet" on the right pane side make sure "Allow Fast Web View" is Checked.

[Enzo]

As a computer-phobe, I can try that with trepidation.

So there is no way to do it with the stock reader then?

Thanks for the upload Gonz, but the file I have includes the one he wants. It would be just before that service bulletin at the end.

[MarkusBass]

Yes, I need version 250-A5 and the file uploaded by DrGonz78 contains only 250-A4. There is a big difference between these two versions: double transistor on the power amp input was replaced by two separate transistors and several resistors were changes or removed. And these resistors are the most important for me. So I'm still looking for A5 version.
Enzo, creating one page from a pdf file is very easy. There are several free programs that can do it. For example PDFCreator: pdfforge.org | The free PDF Creator and Converter It installs as a printer so you just open the file with Acrobat Reader as select "Print ->Select printer (PDFCreator)-> Print Current Page". The program will ask you what should be the name of the file and where it should be stored (and it will contain just one selected page). Of course this Windows application. If you use different operating system, you may need to look for another program.

Mark

[Jazz P Bass]

[QUOTE=Enzo;305439]As a computer-phobe, I can try that with trepidation.

So there is no way to QUOTE]

CutePDF - The free PDF Converter, Convert to PDF for free, Free PDF Utilities.
BullZip: FREE PDF Printer
Both work seamlessly.

[Enzo]

Thanks guys. All those solutions may be simple, but they also all require downloading some new software. SO I am correct that the stock Adobe reader offers no way to take one page out of a PDF and save it separately? I'll try some of that when I get back from helping the wife do something now...

[g1]

Free adobe reader does not allow you to edit pdf's. That's how they get you to buy the paid version .

[Jazz P Bass]

Thanks guys. All those solutions may be simple, but they also all require downloading some new software. SO I am correct that the stock Adobe reader offers no way to take one page out of a PDF and save it separately? I'll try some of that when I get back from helping the wife do something now...

Short of actually printing the file & then scanning it, no.