1. Question: I've built my 1176 but I have a problem...

   Answer: It is a hard thing for a beginner to understand but the fact is that 99.9% of problems can be the result of one or more of the following conditions:

   • Incorrect or faulty components. TEST the value of each resistor and make sure it is correct before putting it in the board. Test each component to the best of your ability before mounting it on the PCB.

     It should be noted that components that are new are seldom faulty. Very often resistor or other values are mis-read either from the schematic, BOM or color code and the wrong component is then installed into the PCB.

   • Poor solder joints. This can include accidental bridging of two or more tracks or pads or "dry" or "cold" joints - ones that do not actually make good electrical contact. Solder joints to external components like pots need to be electrically sound and mechanically secure as well.
   • Incorrect wiring. This can be anything from loose, intermittent or broken wiring, the wrong transformer leads connected, transistors stuck in the board the wrong way or pots wired incorrectly to the board.

   There is a hell of a lot of complexity to an 1176; check your build carefully against the original schematic or if you are unable to do this have someone who can. No drawing or wiring guide is completely foolproof and the original documents have been verified as correct (with the exception of R12 in the Rev D and related schematics).

   You may be able to narrow down major issues to the troublesome section by checking voltages. Here's one schematic with voltages added from Jakob @ Gyraf for the Rev F and later and here's another for the Rev D/E.

   If the fault appears to be in the audio path, you can trace the signal using Mark Burnley's DIY signal tracer hosted by DIY Factory. For other faults it can be useful to check typical voltages in the problem area and confirm them with a working unit.

   If you are unable or unwilling to check the above, the next thing you can do is to use the search function at the Prodigy-Pro forum and see if someone has had a similar problem to yours.

   If you're certain you have a unique problem that no one has resolved post a question to The Lab. The default thread for G1176 problems (mnats Rev J) is All things G1176 - the new "repost" thread. There is also a thread for the Rev A, a thread for the Rev D and another thread for the Rev F. Some kind soul will probably be able to help you out, and others may be able to benefit from your experience.

2. Question: What are the * component values on the G1176-type boards you sell? Which components do I need to put in my board?

   Answer: The components marked * on the Rev J board are optional components not included in the original unit or schematic. If you are using the Lundahl LL1540 input transformer, you need to use two 10k resistors in the places marked R* and R*1 and feed the input level potentiometer from the pad marked *1.

   The values for the other optional components are listed on Jakob's PDF located at http://www.gyraf.dk/gy_pd/1176/1176.pdf. As the components marked * are not part of the original unit you do not have to use them in order to get a working clone. Some of my very early boards had a component marked C*4. This is actually supposed to be C35 and should be included on the board. The value is listed on the BOM.

3. Q: Which components can I eliminate if I want to use the optional OEP or Lundahl input transformer on my 1176?

   A: From the schematic or screen layer of my boards: IC 2; R1-A, B, C, D, E; R3; R4; C*4 (C35); C30; C31; C32; C33; C34; C100; C101. On the newer Rev J boards these components are contained within a line border to facilitate their indentification.

4. Q: Why are there two pad 18s on the Rev J board?

   A: The two pads are to accomodate different sized trim pots. Use the pad that is attached to the wiper (middle lug) of the trim pot you are using.

5. Q: How do I stereo link two 1176 boards?

   A: The short answer is I don't know, I've never done it. Others have though and here's one link: http://www.groupdiy.com/index.php?topic=6182.0 Another way to do it is here.

6. Q: So now how do I match FETs to make a stereo 1176?

   A: Use the search function at Group DIY forum. You might get a thread like this: http://www.groupdiy.com/index.php?topic=1766.msg22468#msg22468

7. Q: Do you have boards in stock? How much is shipping?

   A: Check my Board Sales Page. I will always keep the page updated with the latest information about availability and pricing.

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