Recent content by topher
-
Panasonic SL-CT470,570,590 differences
posted 03-19-2003 08:25 AM CST (US) | Msg Admin: Can anyone tell me if the 590 is as good as the 470/570? I have one of each and have not heard of anything as good. Electronics emall and Amazon have the 470 and 590, but I can not find any 570's.- topher
- Thread
- Replies: 0
- Forum: Portable Source Gear
-
Sony d-cj01 vs d-cj500
Does any one know the difference, especially in sound quality?- topher
- Thread
- Replies: 0
- Forum: Portable Source Gear
-
Cascode Current Source
I want to play with their BJT's as much as the ls-840's. You don't see other 600MHz pnp's with good voltage, let alone good current gain. I sure wish the heterostructure parts would go commercial... Anyway, a price list would sure be nice.- topher
- Post #14
- Forum: DIY (Do-It-Yourself) Discussions
-
Cascode Current Source
ppl, Did the guy at Linear Systems ever give you a price on the LS-480? Or anything else? I asked him twice months before I gave you there address, and I still haven't received a response. He said he would on the phone, but it hasn't happened.- topher
- Post #11
- Forum: DIY (Do-It-Yourself) Discussions
-
Building amps with high speed opamps
Joobu, if you play with a .25 inch drill bit I think you will find that you can remove copper pretty well by hand. It's extremely easy if you remove the copper around a hole in perfboard, but not hard even if you don't have a hole. Apheared, Do you HAVE to show us stuff like that...- topher
- Post #13
- Forum: DIY (Do-It-Yourself) Discussions
-
DIY Equipment Spikes
ppl, What 2 inch mid are you using? I was thinking of a morel mdm55.- topher
- Post #7
- Forum: DIY (Do-It-Yourself) Discussions
-
Skin Effect
aos, You are thinking of the capacitance of center conductor to center conductor. If the "sleeves" are grounded that is _vastly_ reduced, but not reduced much if the sleeves are not grounded. The _amp_ sees twice as much capacitance _to_ _ground_, if you use two lengths and ground...- topher
- Post #20
- Forum: DIY (Do-It-Yourself) Discussions
-
Skin Effect
aos, when I do it, I will use one coax to each driver. That uses the single coax exactly as it should be. If you twisted two coax a little and used the center wires for speaker connections, you would have twice the lumped capacitance, and a LOT more lumped inductance. But I doubt it...- topher
- Post #18
- Forum: DIY (Do-It-Yourself) Discussions
-
Building amps with high speed opamps
Joobu, I think I have seen people cut the copper with an exacto knife and then peel the copper within the cuts... Usually, we just put a piece of tape down. If you want to remove the copper near the inputs to cut capacitance to ground, can you just totally cut away the board there?- topher
- Post #9
- Forum: DIY (Do-It-Yourself) Discussions
-
Skin Effect
aos, Do you want to make a speaker cable or an interconnect? For a speaker cable, I really like ppl's idea. I would love to find out what others hear when they try it. I'll give it a whirl when my speakers are done. For interconnects, I can't see anything being better than using...- topher
- Post #14
- Forum: DIY (Do-It-Yourself) Discussions
-
Building amps with high speed opamps
You liked the sound from that Eval board right? Well, if someone wants to follow your lead, say with a dip opamp, they can build it like this: Get a perf board with copper on one side. Use a drill bit to remove the copper around the holes that the pins go through. Do the same...- topher
- Post #6
- Forum: DIY (Do-It-Yourself) Discussions
-
Skin Effect
Tomo, you seem to be thinking of microwave style wave guide. That has no center conductor and does have modes. Coax with a center conductor handles everything from dc up to a point where at which the dielectric and maybe the outer "conductor" gets lossy. It happens as low as tens...- topher
- Post #12
- Forum: DIY (Do-It-Yourself) Discussions
-
Skin Effect
The whole idea behind coax is that the fields are COMPLETELY inside the outer conductor. The "cross connection technique" is not beneficial. You lose the immunity to outside field interference, and you lose the BENEFITS of the "good" dielectric inside and are in reality using the...- topher
- Post #10
- Forum: DIY (Do-It-Yourself) Discussions
-
Skin Effect
As far as I am concerned, this is NOT how to use coax, not for speakers or anything else. http://www.geocities.com/jonrisch/FIGB.GIF- topher
- Post #8
- Forum: DIY (Do-It-Yourself) Discussions