F2

[Puffin]

I have bought some F2 boards in the group buy.

I want to get this amp right and use good quality and correctly rated components.

I would appreciate peoples views on which makes and type of resistors would be best suited to the F2.

 

[Puffin]

What no-one?!

 

[FYC]

I believe circuit topology comes first, so I am not keen on using exotic components in building my F2.

Resistor rating - please refer to the document in FirstWatt download. I only use industrial grade stuff. For DIYer, Digikey can be a good source.

Once you build it using standard components, I believe you got the majority of the performance level set. Playing around with components are then more of a personal taste or choice.

 

[nigelwright7557]

I have bought some F2 boards in the group buy.

I want to get this amp right and use good quality and correctly rated components.

I would appreciate peoples views on which makes and type of resistors would be best suited to the F2.

Metal film resistors are a good start where possible.

Buy the rest from a high class distributor.

Keep away from ebay !

 

[jupiterjune]

use the vishay/dale metal film -- I think they are the type "RN".

they come in nifty hot dog brown color, so your boards will look like they are covered with tiny wienerschnitzels.

JJ

 

[Puffin]

O.K sounds like a good idea to me!

 

[Tea-Bag]

I user RN55D from mouser for most resistors. They are usually less than 10 cents USD.

If I go big bucks, I use PRD 1/4 watt for signal path, and mills for Power resistors.

I plan on Panasonic power resistors and RN55d for the F2...

 

[toufu]

By the way, what should the voltage rating be for the caps?

 

[Tea-Bag]

By the way, what should the voltage rating be for the caps?

When properly loaded fromthe 24v power supply, the onboard votage of the F2 is ~20v. I think the L1 brings the V down. I would feel fairly safe with 25v ones.

 

[toufu]

Cool! Thanks!

 

[Puffin]

Can anyone tell me the thermal rating and rough size of the heatsinks required for the
F2?

Can anyone reccommend a source that I can get these from?

Conrad heatsinks in Aus would be good because of the excahnge rate!

 

[Nelson Pass]

The First Watt product is about .33 deg C per watt on each
side.

 

[Tea-Bag]

get yerself some Conrads,
MF35-151.5 will do plenty of current Firstwatt amps.

 

[Puffin]

Thanks. Someone else has reccomended them. I missed the group buy though!