Hello friends of the Atari 8 bit computer
Those of you who have visited the JHV¹ already know (unless you fall victim to a lack of interest) that it is possible to upgrade the 1050 in such a manner, that "frying an egg on the heat sink" will finally become a thing of the past.
Some of you will justly notice, that such upgrades have already been in existence for a while. But this one has the advantage, that instead of the old voltage regulators, new compatible parts will be used. Without the need to modify the case, some funny wires sticking out the back or a different power supply.
The power consumption will drop about 25 percent and the only component that still heats up the heat sink, is the Darlington transistor of the rpm control. Both new voltage regulators don't need any cooling.
The upgrade is quit easy: The two existing voltage regulators (7805 and 7812) need to be unscrewed and desoldered (three pins each). Just in case I ever need them again, I screwed them to the other side of the heat sink.
The new voltage regulators need to be prepare a teeny bit. They are pin compatible, but the pins are a bit to far to the front. I just bend them backwards close to the casing and then bend them back down in such a manor, that the distance from the back is about the same as it was on the 78ers.
Solder them in (don't mix up 12V and 5V). Put the floppy drive back together. Finished.
Partnumbers for both parts are:
- TSRN 1-2450
- TSRN 1-24120
The DC/DC convertors by TracoPower (tracopower.com) are sustained short circuit-proof and have a 96% efficiency rate (according to the data sheet).
At the moment they are for instance available at Reichelt² for approximately 8,95 euro³. This will not spare your wallet, but it will spare the environment because of the reduced power consumption as well as the 1050 because of the elimination of the heat normally produced.
Very few Atari's will probably be ever used in such a manor, that the money invested will ever be payed back in less power consumption, but then again, maybe a kilowatt hour will soon be as expansive as a liter of gasoline.
Have fun with this little project
Your FloppyDoc
Erhard Pütz
December 31st, 2012
This article was first published in ABBUC Magazine #112. It was translated by Mathy van Nisselroy with permission of Erhard Pütz.
¹: annual meetings of the members of the ABBUC.
²: An online electronics store of German origin.
³: Prices have gone up quite a bit. According to Erhard the TSR 1-2450 and TSR 1-24120 (no "N") will do just as well since we do not need the ability to create negative voltages. The TSR's are actually a bit cheaper then the price mentioned in the original article by Erhard.
Since the XF551 uses the same voltage regulators, the upgrade should be possible there too. But you'll probably have to temporarily remove the heat sink to get to the 7805. The upgrade might especially come in handy if you have installed a Dual Drive Upgrade by CSS. But in that case, you might need the 3 Amp version instead of the 1 Amp version mentioned here.