This information is extremely helpful! I bought this pre amp and sister power amp in 1972. I can't remember whether it was $50 each or $50 for the pair. They got me through college and beyond but were replaced . . . I recently started listening to them and just replaced the selector switch...
The PC-5 board is the "line" board as opposed to PC-6 which is the phono board. PC-5 is powered by eyelets 16, 18 and 19. They all come from the Capacitor board and eyelet 16 is the high voltage and currently measures 500 volts. 18 & 19 are the low voltage lines. The schematic shows the bottom...
Here is a photograph of the inside of the Dynaco PAS-3 preamp without the tubes. I was afraid to install them with 500 volts showing. The two red wires are the 300 volt secondaries. The centertap to these is grounded to the chassis underneath and the two blue wires are what was represented as...
The transformer is sold as a PA211 Power Transformer. You seem to be more familiar with these than I. It would be helpful to me if you would search for one of these to check the accuracy of my statements. I could certainly use your experience. I will see if I can upload a photograph of the...
I would like to disconnect the secondary windings from a stereo preamp to test the voltages of the secondary windings. The transformer has a 330 - 0 - 330 volt center tapped secondary and a 10.9 volt secondary. It is to be used with house current - 110 or so in Virginia. I have measured the...
An online seller claimed with an 80 Cubic Feet per Minute blower his output temperature was 350 degrees Fahrenheit from a fireplace heat scavenger. If you assumed his measurements were correct and the room temperature (input) was 70 degrees F. how would you calculate his gain in British Thermal...
I have constructed a gain clone type amp based on the LM3886 chip from Texas Instruments. I have wired it using some available 16 gauge stranded wire. It is powered by a centertapped 34 volt (68 volt total) transformer that is fused by a 2 amp fuse. It is working with no issues however I would...
I have purchased the parts and am about to assemble. I don't understand enough about:
A. Does pin 4 & 8 get powered from +12V & -12V looking at box A?
B. Does pin 4 & 8 get powered from +12V & -12V looking at box B too?
My question is does the OP AMP need this power at both places?
C. & D. Is...
Berkeman: My intent is to cut a piece of metal to cover the space left when Dish supplied much smaller components. I would then attach the ground wire from the outlet to the metal plate. I would use 2 potentiometers to simulate a balance. I would then rely on the metal plate to conduct ground...
Davenn: CD1 & 2 at 15V min - Thank you. As to RL1 at 820 ohms what wattage would you suggest?
You said:
yup, CN1,2 are useless where they are
1) they are going between rails instead of from each rail to 0V rail
2) and they should be right at the output pins of the reg. chips
Am...
Advertising? My name being McIntosh (the apples, the high grade stereo equipment and of course the computer) if I had hit on only one of the three I would be able to just purchase a preamp.
As to Berkman, yes, the video shows a 35 V capacitor after the rectifier. The rectifier, voltage...
<< Video Link Deleted by Mentors >>
You will quickly learn I am not the brightest bulb on the tree. I hope this will get you to the video. At the video if you scroll down and click on the "Show More" there is a link to the schematic. Thanks
I found a preamplifier (audio) described by the designer on his YouTube video. He posted the schematic with the units of the parts (ie. 3300uf) but he left out the rating, at least I can not find it. Here is what I think I want:
1. The designer is << Website Link Deleted by Mentors >>...