Thread: Contacting Mucha....

Originally posted by rbarr110
I have tried to email mucha without success (has like 3 different emails).

ANyway if you are out there Mucha here is the email I have sent to you.

I am very interested in acquiring your MPBS1 rev B supply. I have been spending some time in the mp3car forum and found your web page and PSU. Could you please tell me what the rev B update is, I didn't see anything about rev B on your webpage. Also is the supply a "complete" ATX supply?

I am also interested in your shutdown controller.

Thanks
Ryan

The new improved microcontroler shutdown unit will be ready soon! I promise!

I do have several MPBS1 B s ready to ship. The only difference between rev A and B is that I made the layout easier, The +12 volts is more efficient and you can connect power to the supply and it won't trigger the mains. Before, if you connected power to the supply, it would turn on for a second before the caps charged up and would turn on the computer for a second, which didn't hurt anything, I just found it annoying. The specifications on the supply didn't change. It is just improved, when you build up ten of these, each one taking you 6 hours, you find ways to improve them...

I am selling them for 159 plus shipping. I prefer paypal, but I am open to other methods..

Jeff

Originally posted by rbarr110
Also is the supply a "complete" ATX supply?

By complete, do you mean better than the ATX versions of the sproggy? Yes I believe so.

Or if by complete, you mean that it will power a 70 watt AMD XP 2000+
In that case the answer is no.

Is it as complete as a DC-DC supply from Arise or Keypower?
No, but it has 1/3 the volume, and is more efficient and will operate on lower voltages. It is as functionally complete as it will behave just like a regular ATX power supply. It has soft power off, standby voltage, power good, etc. And I built those signals to the ATX spec. with proper switch debouncing.

I notice that you don't connect all the wires on the ATX connector?
There are a lot of redundant wires to lower the resistance between the power supply and the motherboard. The 18 gauge wire has no problem delivering 5 amps to the motherboard with just one wire with the cable I use. The redundant wires are a requirement with longer atx cables (> 12 inches) and higher power motherboard/cpu setups.

Do you at least connect all the signals?
Yes, I connect +12 +5 +3.3 -5 -12 PS_ON, PS_OK, and +5standby

Or does it have a fan? No, but you can connect a cpu fan right to the unit and power it from the jumper on the unit.

Does it have a complete enclosure? No

Do it have a fuse and reverse voltage protection? Yes 10 amp automotive fuse.

Have I tested it for EMI? No

Do I provide more than one hard drive connector? No but I can.

How long is the ATX cable? about 6 inches from the unit.

Do I need a fan? It depends on how much air flow you will have.

What processors do you recommend? Celeron 566-800 or Pentium3 566-800. OR VIA motherboards with low power embedded processors.

Can you use it with slower processors? Absolutely! It will power most Pentium 100-233mmx processors with motherboard and hard drive no problem.

What about Pentium Pro? No. Even though they are slow by today’s standards, they draw about 30 watts.

How many watts should the processor draw?
I would suggest less than 20 watts because most get the power from the +5volts, and I only provide a peak of 6 amps on the 5 volts. That is 30 watts total for everything.

I found a 1.5v celeron 566 and a 1.7 volt celeron 566. Will I save power with the 1.5v? Yes you will save on the order of 4 watts by using the lower power CPU.

Do you provide a way to use it as an AT power supply? Yes. you can use the optional power on jumper/button as the power switch. You will have to request that I don't connect the power cables or send me the AT MOBO connectors you want on it.

Why do you charge so damn much money for this supply?
Because at 10 dollars an hour for the price that I am charging, I question weather or not it is worth my time at all. It takes a long time to build one and I haven't found cheaper labor yet.

Have you tested the supply very well yet?
Yes, to the extent I have been using it in my car for a year now and I love it, it never reboots the machine when I start the car.

Do you offer a warranty?
Because of the hobby nature of this product, I can not offer a warranty or accept any liabilities if your application of this supply causes any damage to your car. I encourage you to test the supply for cooling requirements and I require that people using this supply have the technical aptitude to do their own custom installation.

Are you going to start an MPBS1 FAQ? Yes.