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ClaveFremen 28th July 2012 01:32 PM

My_Ref Fremen Edition RC - Build thread
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Hi all,

in this thread we will discuss about building the My_Ref Fremen Edition using the Release Candidate boards.

We also discuss listening evaluations and, eventually, further improvements.

I've attached schematic, silkscreen and BOMs

To build it you will need:
  • soldering iron
  • thin solder
  • tacky flux
  • tweezers
  • a good sight or a magnifier ;)
In the next posts I'll illustrate my build as a tutorial.

ClaveFremen 28th July 2012 01:50 PM

1 - SMD parts
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Clean boards with alcohol.

The first component we put in place is the LM318.

Apply flux to pads:

Then position the LM318 (take care to pins to pad alignment) and keep it in place with tweezers:

Apply the wet solder tip to one of the pins (the bottom one on the right is NC so it's a good one to use)

Now that the LM318 is kept in place by the soldered pin we solder all the others.

Just apply the solder and solder tip for 1-2 seconds

This should be the result:

ClaveFremen 28th July 2012 01:59 PM

4 Attachment(s)
We then proceed with 0805 compensation resistors and cap, starting from C34.

Apply flux:

position the component and while keeping it in place with tweezers apply the wet tip to one side.

then apply solder and tip to the other end


ClaveFremen 28th July 2012 02:04 PM

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after applying flux to R39 we solder it like we did with C34

Same tecnicque for C43

Note that marking on resistors follow the same direction of the arrow

ClaveFremen 28th July 2012 02:12 PM

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The next component will be the MELF diode D3.

As usual apply flux, keep it in place using tweezers

and apply the wet tip to one end (for melf you'll need a well wet tip).

Apply solder and tip to the other end.

This should be the result

Now, like we did for LM318 we proceed with D1 and D2 (flux, solder one pin while keeping the part in place with tweezers, solder the other pins)

ClaveFremen 28th July 2012 02:16 PM

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Now the we know how to solder SMD parts and made some experience, we proceed with all other resistors (pay attention to orientation)

Note that 3K3 resistors are 0805 ones soldered on 1206 pads.

Mouser don't stock in this moment 1206 3K3 Susumus so in BOM 0805 ones are indicated.

ClaveFremen 29th July 2012 01:45 AM

2 - Trough hole parts
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I suggest to mount standoffs before starting this phase.

Screws will stabilize board when it's reversed for soldering

The golder rule is starting from lower profile parts so we'll start from DC protection resistors.

Using pliers to bend leads helps to obtain a nice looking build.

Solder parts on both boards, alternating them, it would be easier and let parts cool.

After bending leads mount the resistors in posistion and turn the board

Then solder first one side of both resitors

Then proceed with other side after the second board is done.

Proceed with other 1/4W resistors

Note that I've left unsoldered thermals pads, we'll do the same for all thermals so we can solder them later with a higher soldering temperature.

If possible keep same orientation, it will look better

ClaveFremen 29th July 2012 02:03 AM

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Next lower profile components are the 14V zeners, bend leads first

Use same tecnique used for resitors (mount parts, turn the board, solder one lead for each part, do the same on the other board, solder the remaining lead)

Then solder the 1N4001

We can start with 1/2W resistors, from R10

Note in the next picture the correct orientation the gold (tolerance) band represent the point of the arrow.

In this phase you should choose which C9/R10 arrangement to use.

I suggest the new one

Note that Rikens have opposite orientation (tolerance red band goes opposite to the arrow)

KOA SPR orientation, note that the marking on board have same orientation of the one on resistor.

Note the thermal pad left unsolderd also for the KOA...

This is the lower profile parts soldering result

ClaveFremen 29th July 2012 02:17 AM

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Next part to solder is the led.

Silkscreen it's not clear on led orientation, the silkscren file help us

Sadly the led in BOM doesn't have the dent so we should use leads leght to identify anode and cathode, the right orientation should be this one.

To solder it keep it in place using fingers

ClaveFremen 29th July 2012 08:21 PM

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A further note on LED, traces of LED's pads and external LED connectors are parallel so for those that want to use the connector use same orientation.

Let's pass to transitors.

:att'n: there are 2 types of BC639 in BOM: BC639-16 (regulator) and BC639G

I choose to start from DC protection ones

When soldering transistors solder one single lead for each

Then solder other leads alternating transistors so to not heat too much parts.

As usual leave thermal pads unsoldered.

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