Roender's FC-100 prototype and builder's thread

[lucylu]

Hi One of my emitter resistors is very loose in its ceramic white case will this cause problems cheers john

[RKH]

I had a similar issue with one of my resistors. I suspect that the problem is due to too much heat applied when I soldered it in place. I would replace the resistor. Better safe than sorry.

Also, there is a fine grit that comes out of the loosened resistor. I also recommend you look for that and thoroughly clean the board.

I tend to take a more cautious approach to these things. YMMV.

Ryan

[Rudi_Ratlos]

I have finally finished the layout of the "supplementary audio PCB" and have ordered a prototype PCB:



The size of the PCB is 100 x 100 mm and it includes:

- a 3-source selection (top left)
- a mute relais
- George Stantscheff's Lightspeed Attenuator (top right)
- 2 temperature sensors (LM35) (below the attenuator)
- LCD connectivity
- infrared sensor
- Motor-H - bridge (for motorized potentiometer adjusting the attenuator, on the bottom)

The heart / brain of the PCB is included in a PIC 16F886 µProcessor, and the PCB's functionality is controlled by an infrared remote control unit.

This PCB is of course intended to work together with my FC-100.

I do not yet have much experience with the programming of µProcessors, but I will learn it, and maybe, in a month or so,
I will be able and offer you (if you like) this PCB.

Best regards - Rudi_Ratlos

P.S. John, Ryan: I have never had any problems soldering MPC74 - type - resistors.

[claus1968]

Rudi, when the time has come, I will be in.That's something I need

Claus

[mj777]

nice work Sir Rudi, count me in if you offer this pcb in the group buy.

regards,
mj777

[miepa]

hi there,
i`m interested what exact type of resistor you guys use to built the FC-100 ?

did you all go with the - Yageo Metal Film Resistors (Professional) Type MF0 Series ??
thank you.

[atupi]

Good question Miepa as i'm preparing to order some parts for my MP-100.

[Telstar]

Ok since this is the builders thead I have a question about those elusive 2.2R resistors.
How much tolerance can the circuit stand without ANY degrade in performance or stability?
I'm asking this because maybe we can find 2.21R or 2.1R from the usual sources.

On a different project I'm working on presently, I changed .47 output resistors with .5 to get them of a better quality.

[roender]

Originally Posted by Telstar

Ok since this is the builders thead I have a question about those elusive 2.2R resistors.
How much tolerance can the circuit stand without ANY degrade in performance or stability?
I'm asking this because maybe we can find 2.21R or 2.1R from the usual sources.

On a different project I'm working on presently, I changed .47 output resistors with .5 to get them of a better quality.

Anything between 2 and 3 ohm will be ok.

[Telstar]

Originally Posted by roender

Anything between 2 and 3 ohm will be ok.

I did another search on Mouser up to 2.5 ohm, and still nothing available. I had to up the power to 1W to find something.
If you can/like mount vertical there are a few that could work.

This is the closest match:
CPF12R2100FKB14 Vishay/Dale | Mouser

Hope this could help u guys.