[hell0un1verse]

Hi there, I am assembling a STEPS PSU, a simple question here, do I need to solder the heatsink on the board, of course I have soldered down the pins of LM317. Thanks.

BTW, following are the measurements I got on the board:
TP1 and TP2: around 36.1V
TP3 and TP5: around 47.3V
PSU set at 27V

My transformer is Amveco 70053, Tangent mentioned in his instruction that 40V was obtained, but mine is only 36V, Do you guys see problems here?

Thanks.

 

[vixr]

I soldered mine down... It mostly keeps stress off the regulator's pins. That's a pretty massive sink... The pads aren't connected to anything. Tangent says he measured "around" 40 volts...

 

[raduray]

I'm gathering parts to build one as well, also for 27V, but can't find the 70062 or 70052. I actually prefer the '62 as I need to provide current for the M3 at high bias and I think I need the additional headroom the '62 provides.

I've read the 70053/65 results in lots of heat when adjusting teh regulator to 27V. You're dropping approx 10V across the regulator and if you power a high power amplifier, like an M3, then you might have excessive heat.

Of course, the 70053 is available from Digikey while neither the 70062 or 70052 are. DigiKey told me the '62 has been on backorder for 22 weeks.

Radu

 

[hell0un1verse]

Oops, I didn't notice that AMB actually used a 70062 in his STEPS for M^3, mine does generate pretty much heat.

I just soldered the heatsink down, pretty big bulby joint

So seems that I need to tap the heatsinks of M^3 and solder them down too.

 

[mb3k]

The regulator does actually get quite hot as well as the heatsink.
There was a previous thread about how we all hate soldering it down, and it would be better if it were a screw-down type of heat sink.

 

[Windchill]

Quote:

Originally Posted by hell0un1verse Oops, I didn't notice that AMB actually used a 70062 in his STEPS for M^3, mine does generate pretty much heat. I just soldered the heatsink down, pretty big bulby joint So seems that I need to tap the heatsinks of M^3 and solder them down too.

Don't think so. If you tap the heatsinks for the M^3 you can secure them with screws rather than soldering them. I did that using 4-40 screws and it works great.

 

[hell0un1verse]

Oh yeah, I actually meant that.

 

[ozshadow]

Perhaps you should try this instead for a heatsink mount:

http://www.arcticsilver.com/arctic_s...l_adhesive.htm

 

[hell0un1verse]

Ha, glew, that's nice, I don't have tool for tapping, that's why I hestitated. Thanks.

 

[Windchill]

Quote:

Originally Posted by hell0un1verse Ha, glew, that's nice, I don't have tool for tapping, that's why I hestitated. Thanks.

I picked up a little 4-40 tap and drill bit pack along with a handle for the tap at Loewes for $10-15 total. Worked fine and it's a common size. Seemed reasonable to me.