sprocket Posted May 10, 2003 Share Posted May 10, 2003 Erik You freak me out with how helpful you are. What an outstanding citizen. Are all you Texan folk this cool? I like the complete and clear description of the problem you give, Leok too. Like Tom M, I enjoy the ride. Cut-Throat and Ed great pictures. Wish I knew how to picture my M-dogs here. Kelly (Mobile-Homeless) put mine on the forum a while back before he pulled the rip-cord. I haven't a clue how to do it. Cut-Throat, I assembly instruction and schematic for the M-Dogs if ya need them? RB Quote Link to comment Share on other sites More sharing options...
edster00 Posted May 10, 2003 Share Posted May 10, 2003 Sproket you have a PM. Quote Link to comment Share on other sites More sharing options...
Cut-Throat Posted May 10, 2003 Author Share Posted May 10, 2003 RB, Thanks for the offer of the manual and Instructions for the Moondogs. - I need them Bad! I would appreciate it. Erik is a peach of a guy. -It's definitely not because of Texas.:bigsmile:] Erik, Thanks for all your help. Your instructions are impeccable and better than I've received on any kit I've ever built. I'll finish the mod tomorrow and let you know. Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted May 10, 2003 Share Posted May 10, 2003 Kudos, RB (think I got those two letters right!) I can also copy a schematic if you need it -- I should have mentioned this before. You NEED to have one for future reference. Let me know, Kevin, how things go. Have fun! Well get the other couple of things done in due time. A very enjoyable conversation with our fellow member, Cut Throat. He's got me curious about the 300B Billie amps! I bet they sound really good. Erik Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted May 10, 2003 Share Posted May 10, 2003 Lots of thanks to Edster for posting an example of is always-really great digital photography! I must learn how to do some of that. My photographic skills are still locked in the dark room with SLRs! I appreciate this, Ed, in that it makes much clearer things that would take far longer to put into words. Notes on a great little (slightly mis-aligned) tuner tomorrow. Erik Quote Link to comment Share on other sites More sharing options...
sprocket Posted May 10, 2003 Share Posted May 10, 2003 Cut-Throat I have a package to sent your way. Drop me a PM with a address to send it to. Ed, thanks for the offer to help me with pictures. I just looked again at the shot of your amp with the cool lighting and the sparkling Mullard rectifier tube. Double wow. Feel free to post it again so we all can appreciate the beauty of the Moondog amp. RB Quote Link to comment Share on other sites More sharing options...
SpikeJampton Posted May 10, 2003 Share Posted May 10, 2003 As far as I'm concerned, this has been one of the best threads in months on this board. So much information! I have a pair of Moondogs with the ultimate upgrade and I couldn't be more happy with my purchase. Erik, whereabouts in Texas are you? Quote Link to comment Share on other sites More sharing options...
Erik Mandaville Posted May 11, 2003 Share Posted May 11, 2003 Hi Kevin: As mentioned in my earlier email, there are a couple of things I think would be good to look at in greater detail. Your report on much quieter hum is encouraging, but we might be able to do even better! 1. Examine the ground connection on the RCA jack. The way this was done, as far as I can see in your pictures, is not the usual way of carrying out this important connection. To do this properly, you may have to partially remove the back panel that holds that jack, IEC connector, and binding posts. The RCA jack is easy to remove, but support the body of it from the inside as you remove the nut from the outside -- a good grasp with sturdy long nose pliers should do the trick. But use an open ended or crescent wrench on the nut to avoid damaging the finish. The RCA jack connections should include: a)center conductor of coax (securely) connected to center pin of the jack.(when I make this connection on a project, I usually make two turns of the center conductor around that pin, crimp lightly, then solder. I have found that just inserting the conductor into the hole can sometimes make for a superficial connection. This is just a personal style and choice, though. b)The braided shield should be neatly twisted and attached to the body of the jack, as should a black wire that connects to the main circuit ground bus. Redo the above connections if they look poor or 'cold.' * You will find that when soldering, the jack functions like a heat sink, and it takes a very hot iron to get it hot enough for proper soldering. If things look basically ok, leave it! Go on to check how the black lead from the jack connects to the circuit ground. The way it was done in the picture looks strange to me. That lead should go DIRECTLY from the jack to one of the ground lugs on the main terminal board. There should ideally be no other wire or connections involved. Lastly, Remove the transformer bolt/s that hold the ring terminals to the chassis ground. Check to make sure that the clear coat enamel that was sprayed on the chassis has been carefully scraped away and removed from the point at which the ring terminals make contact with the chassis plate. This is important, and something which the Moondog construction manual (at least mine) does not mention. Metal to metal contact in this location is crucial to a good ground connection. Use a star washer to make sure its 'little teeth' bite into the chassis for a good, solid ground. One other thing that might be of interest to try, which both Leok and I have done (by way of slightly different approaches) is to float the circuit ground ABOVE the chassis. This simply means that the primary circuit ground that connects to the chassis (as mentioned above) by way of a ring terminal is removed. To do this on a temporary basis to see if it lowers hum and noise levels even more, just remove the ring terminal that connects to the main terminal board. Reinstall the transformer nut and star washer, keeping the safety earth ground where it is. The circuit ground ring terminal can be held to a non-grounded or circuit-related place with a ziptie or piece of old shoelace. Use a white shoelace. I have experimented with other colors of shoe lace, and all of them seem to reduce the frequency response of the amplifier. By lifting that ground connection, there is only one point at which the preamp/amplfier circuit (as one is really part of the other)is grounded -- at the lower impedance, preamplifier end. This may or may not help! Also: It can sometimes be very beneficial to solidly ground the body of the volume controls on an amp/preamp. On my AES AE-1, there was black paint both in the hole for the volume pot shaft, as well as on the front and back of the panel in that same location. The volume control was grounded, but poorly and unreliably. With an X-acto knife, I carefully scraped away a neat and circular area (the size of the washer on the pot)on the back of the panel where it makes contact with the body of the volume control. This made a noticeable improvement! Ok. That's going to be it from here today. Time to take my dogs out for a walk, and then save some energy for yardwork. My wife and also have our weekly visit to Barnes and Noble and Starbuck's, where we each get to treat ourselves to a new CD! I can't wait for school to get out for the summer. Teaching is good, but by this time of year is akin to crawling on one's knees to water in a desert! Erik Quote Link to comment Share on other sites More sharing options...
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