gar2520 build thread

[jsteiger]

bigevil, I don't see Q6 on the build?

Also, double check all transistors to make sure the right part is in the right place. I have heard of some peeps swapping the larger BD's and/or have them turned 180 degrees. Also recently had a guy have a 550 and a 560 swapped.

 

[bigevil]

Jeff,
thanks for the tip. (the first batch of photos were taken before I had Q6.... one of the legs had broken off but Gary sent me one). I'll double check all of the transistors now and see where we're at!
Thanks much

 

[jsteiger]

the first batch of photos were taken before I had Q6.... one of the legs had broken off but Gary sent me one...

Ah, OK. I suppose that missing was a bit obvious! 

 

[bigevil]

AHA! Q7 & Q8 were swapped.
going to desolder/ resolder now and test.

will report back!

 

[bigevil]

well, unfortunately after closer examination it seems like two of the small diodes cracked and burned up. the board is so small that I feel like its easier just to start from scratch than trying to de-solder and fix everything. I'll order a new one and start afresh! thanks

 

[windgassen]

I am using this board as an educational device to learn about building op amps.  I have purchased the kit and received the build instructions (which are very good !!)  Only thing that disappointed me is that there was no schematic included.  Any chance you would be willing to share the schematic for this unit ?

Thanks !!

Jim

 

[Synmaster]

Could anyone send me pdf assembly guides for gar2520 and gar1731 please? Jeff seems to be unreachable by email for some reason, and without these DOAs my current project has come to a halt.

 

[jsteiger]

Could anyone send me pdf assembly guides for gar2520 and gar1731 please? Jeff seems to be unreachable by email for some reason, and without these DOAs my current project has come to a halt.

Ivan?? I sent them yesterday, for the 2nd time. Check your spam folder. I replied to your email as well. Maybe something is funky with the email service from me to you? 

 

[Synmaster]

Could anyone send me pdf assembly guides for gar2520 and gar1731 please? Jeff seems to be unreachable by email for some reason, and without these DOAs my current project has come to a halt.

Ivan?? I sent them yesterday, for the 2nd time. Check your spam folder. I replied to your email as well. Maybe something is funky with the email service from me to you? 

Jeff, that's really weird... my spam folder is empty, furthermore everything @classicapi.com is put to my trusted list. I received all auto-generated order related messages no problem. PMed you my alternative address.

 

[jsteiger]

Could anyone send me pdf assembly guides for gar2520 and gar1731 please? Jeff seems to be unreachable by email for some reason, and without these DOAs my current project has come to a halt.

Ivan?? I sent them yesterday, for the 2nd time. Check your spam folder. I replied to your email as well. Maybe something is funky with the email service from me to you? 

Jeff, that's really weird... my spam folder is empty, furthermore everything @classicapi.com is put to my trusted list. I received all auto-generated order related messages no problem. PMed you my alternative address.

I do send the support docs out from my personal Yahoo email address. Maybe that was trapped in spam? Anyhow, I did just send them to your newly provided address. Hopefully you already have them! 

 

[Synmaster]

I do send the support docs out from my personal Yahoo email address. Maybe that was trapped in spam? Anyhow, I did just send them to your newly provided address. Hopefully you already have them! 

Got em! Thanks Jeff, quick and hassle-free this time! Will check if my mailbox blocks yahoo... who knows. And now I'm just a few (albeit important) steps from finishing my love child. Many thanks again! Will do some fine soldering tomorrow

 

[kante1603]

Hello,

just wanted to say a big thank you to Garry (and Jeff of course) for this DOA.Have build another 30 pieces now (already did some in Jeff´s VP28 and Lovechildren builds) and found the time to measure them today.All up and healthy,just 1 cold solder blob from more than two and a half thousand,not bad.
Here´s a pic of my little treasure chest.

Best regards,you guys rock!,

Udo

 

[gar381]

Looking Very Good Udo and
Thanks for your kind words..

GARY

 

[okgb]

Bond ............ G Bond  ............Plus a few from our Italian friend Pier ?  Looks good ! [ I'm jealous ]

 

[kante1603]

Haha....good eyes!APP992s for different projects.

Thanks for watching,

Udo.

 

[voidar]

Not the first to do this, but I think I butchered my two 2520s by being ignorant to Q7 and Q8 being different .

Not catching this R11 would smoke up and Q7 would actually melt the solder (the transistor moved under its own weight)!

Swaping them to their correct place would have R12 smoke up sadly, which leads me to believe some other componenst must have failed at first (although some browning, R11 and R12 still measure ok). Quite impractical to troubleshoot this thing.

Just another warning to any novice .

 

[jguitar]

All right this is my first post here. I have been in contact Via email with Jeff Steiger  about my smoking 2520. I told him if I figured it out I would post so that others won't make the same mistake I did. So what happened was both the 56 ohm resistors burnt (although after I took them out they still read the correct resistance). Someone posted about this earlier in this thread but there was no follow up as I think they started fresh with a new kit. Well after pouring over this tiny little board I found my mistake. I had assumed that the two transistors that come attached to the small cardboard piece (Q6 and Q9) were the matched transistors Q1 and Q2. They are definitely not as most of you already know. I told myself I wasn't going to make a mistake when I started that project but I did anyways. I'm fairly new to this so this mistake was a good learning mistake. Hopefully somebody will find this useful for trouble shooting. My VP26 is now up and running and sounds great. I went ahead and got an assembled GAR2520 and another Kit. Both work great. Had a lot of fun putting these together and can't wait to get to work on another.
Thanks Jeff and Gary for such a great product.

Tim

 

[voidar]

Q1 and Q2 are NPN transistors while Q6 and Q9 are PNP. That is a serious blunder, like what I did with Q7 and Q8.
I doubt swapping the matched transistors with the other BC550Cs would make any smoke.

Anyway, what did you do, replace or swap the parts?

 

[jguitar]

Yeah it was a bonehead move on my part. I did not discover this mistake until after I had ordered another Gar2520 kit plus a prebuilt one. The second kit I built worked fine. I did manage to desolder the offending transistors (this took a long time and was no fun) and swap them around but I have not replaced the burnt out resistors as I have not got any spares lying around of the exact value. I'm not sure if it will work as I don't know if I have ruined the transistors but I'm going to try just for fun anyways.

Tim

 

[tonycamp]

Hey Fella's,

Anyone have the build guid pdf for the 2520's? I picked up 20 Gar-opamps 10-1731s and 10-2520s from jeff, but did not receive the build guide, jeff tried to send them from the road(he's traveling i think), but it didn't work. I managed the 1731's without the guide, but the blue ceramics are not visible in any thread i've seen.

thanx
Tony