garxxxx(OA10) support thread New
« on: August 08, 2019, 05:59:05 PM »

There are a few part # errors in the BOM in the current manual.

R2 & R5 is 2.7K  the correct part # is
MOUSER 271-2.7k-RC ( NOT 271-2.7-RC)

R9 is still 3.3R  1/2 watt                                                               
MOUSER 293-3.3-RC
(NOT 291-3.3-RC)

CD1 & CD2  Part number should be
594-K104K15X7RF5TL2 (NOT 594-K104K15RX7RF5TL2)

There will be an updated fixed manual soon in the doc section at the CAPI store.
Look for REVISED added to the link.

Just another note here..
Mouser seems to be having trouble with stock
on R8  (293-10-RC) at the moment.  You can use
660-CF1/2C100J as a sub if necessary.   


The NEW garxxxx(OA10) DOA will work from +/- 15V  thru +/-24V so it is a
Happy camper on any VPR or 51X standard.  More info to come soon!!


Either print it out or have the pdf open on your desktop. This will help both the novice and ProTech alike
from accidentally making assembly errors.

Note that the OUTPUT transistors are NOT the same.  One is a NPN and the other
is a PNP.  Make sure that they are in the correct positions and facing the correct directionAs shown in
the assembly manual.

Note the BLUE Murata caps are all different values.  Make sure you got the correct
cap in the correct positions as shown in the assembly manual.

Note that the DIODES are polarized.  Make sure that the black band on the diode is in
The hole with the circle.  Note the diode pads on the PCB are square shaped. 
They are the ONLY square pads on the PCB.

All  BC560C transistors are on tape.  (Except for the Matched Pairs on the
gar918BC and garxxxx(OA10) kits.  These are in a little bag with the milmax pins.)
The pads on the PCB are in a straight line on ALL The BC560Cs and only these,
so that they
will not be confused with the BC550C pads.  Make sure they are facing the correct way as shown
on the silkscreen.

All  BC550Cs transistors are in little bags.  One of the bags is for the
MATCHED input pair (gar2520, gar1731 garAM10kits) and this bag will also include the Millmax pins. 
Do not remove the transistors from this bag until installing them so they do not get mixed up with
the other BC550C transistors in the kit.  All BC550C pads on the pcb are in a triangle formation
so as not to be confused with the straight line BC560C pads. Make sure they are facing
the correct way as shown on the silkscreen.

Measure all RESISTOR values at instillation and install according to the manual. 
Be careful when measuring values above 100k so you will not be including your skin
resistance in the measurement.

Before testing your fresh assembled DOA,  double check for unwanted solder bridges where shown
In the manual and make sure that no component leads on the component side of the PCB are
touching each other.

As these are all the most common assembly errors.  Following this basic informational
Guide should result in a successful build and your new DOA should work first time out of the box.

If you followed the Assembly Tips Page and Assembled your DOA by this
Manual all should be well and it should work the first time “out of the box”
But even the most experienced of us have an occasional screw up.


Note on part substitutions in kits.  Occasionally the parts listed in the BOM
Of each kit maybe temporarily unavailable from my parts supplier.  A substitution
Part will be included in the kit.  These parts will be of the same value, tolerance
And quality of the part listed in the BOM.   

For you folks sourcing your own partsFor your builds,   All the ¼ watt resistors use
any major brand 1% metal film. The ½ watt resistors can be any major brand carbon film
or metal film 5% or better.
The Murata caps can be 50v or 100v 5%.  Any major brand npo/cog 5% with the lead
Spacing of .1” or 2.5mm can be used if necessary. 
Output transistors can be ON semi, Fairchild or ST micro transistors. 
Note that the ST micro transistors have a slightly different  Package but will drop right
in the PCB just fine.

« Last Edit: August 22, 2019, 09:14:10 PM by gar381 »
RETIRED.....  from 51yrs in Show Biz

gar2520, gar1731,garAM10,gar918 DOAs at
NEW Sphere section


Re: garxxxx(OA10) support thread
« Reply #1 on: August 18, 2019, 01:48:52 PM »
Happy to announce I've got the new garOA10's listed at the store!

You can find them here:
Visit the CAPI store at

CAPI is not affiliated with, endorsed by, or sponsored by API.


Related Topics

  Subject / Started by Replies Last post
2 Replies
Last post September 11, 2007, 04:35:55 AM
by pstamler
1049 Replies
Last post May 29, 2019, 07:10:29 PM
by Leon
9 Replies
Last post September 22, 2014, 05:53:53 PM
by Electrobumps
462 Replies
Last post November 07, 2019, 02:48:36 PM
by jsteiger