unbraiding shielding
Got another beginners question. After stripping off the outer pvc sheathing, on mic cable, I used a sewing needle to un-braid the shielding. I started at the tip and worked me way down about 3/4".
After that was completed I had to cut off the many small strands of thread. I then wound the shielding wires together for tinning. I did this to each end of four cables and total time was about an hour. Is there a trick to doing this that would reduce the time.
Thanks
Got another beginners question. After stripping off the outer pvc sheathing, on mic cable, I used a sewing needle to un-braid the shielding. I started at the tip and worked me way down about 3/4".
After that was completed I had to cut off the many small strands of thread. I then wound the shielding wires together for tinning. I did this to each end of four cables and total time was about an hour. Is there a trick to doing this that would reduce the time.
Thanks
panel grounding
Sounds effective and easy. I'll just put a screw between adjacent panel edges that will cut through the anodization. They won't be noticeable and no wires, connectors, nuts or washers. Four to six screws, a continuity check and done.
I use a dental pick type tool (no leverage with a sewing needle, ouch!) and can unbraid in about a minute. My trick is repeatedly shoving the pick under the shield braid lengthwise along the wire axis in several spots around its circumference and then pry open the braiding to enlarge the diameter. (a photo would be worth a thousand words here-think pick and cable in same line with pick pushed in between shield and inner wires) Once braiding diameter is enlarged its easy to comb out the individual strands.
With shielded cable, you need to be a little careful. I usually score the outer jacket first. Just score it or maybe cut halfway through. Then all you have to do is to bend the end of the cable over and touch the score with the knife to cause the jacket to separate. This way you can strip the cable jacket without nicking the shield.
I use a small screwdriver or a scribe to unbraid the shield. It usually only takes a few minutes. I also saw a technique used on some RF cable (RG-179 I think) where a small hole was unbraided in the shield where the shield met the jacket and the centre conductor was fished out though the hole. I've never been able to make that work. You don't need a perfectly unbraided shield. You just need to get the centre conductor(s) out.
Some cable contains thread or other features to make the cable flex more easily. Be careful when you cut these as you don't want to nick the shield or the centre conductor(s).
Regarding your question about applying contact cleaner to the wires before inserting them into the terminal blocks: Unless your amp is going into an unusually harsh environment (automotive, marine, etc.) I wouldn't worry about it. I don't think the contact cleaners would hurt (other than your wallet) but I don't think they'd provide much benefit in a residential application.
Tom
A great company
I posted this on the parts section but just wanted to put it here. I have no connection with this company.
I ordered some screws, nuts and washers from ALBANYCOUNTFASTENERS.com. When I didn't get them I used USPS tracking and found the USPS had received them, then no change in tracking for over a week.
I contacted USPS and they were no help. Albanycountyfasteners contacted them and got no useful info.
They called me and said they would ship a duplicate order no charge and free shipping. I told them I needed 3 more 25 pc packs of screws.
They sent a duplicate of the original order plus the additional screws all for free including USPS priority mail. Everything arrived within two days.
I don't think I've ever dealt with a more responsive company.
I posted this on the parts section but just wanted to put it here. I have no connection with this company.
I ordered some screws, nuts and washers from ALBANYCOUNTFASTENERS.com. When I didn't get them I used USPS tracking and found the USPS had received them, then no change in tracking for over a week.
I contacted USPS and they were no help. Albanycountyfasteners contacted them and got no useful info.
They called me and said they would ship a duplicate order no charge and free shipping. I told them I needed 3 more 25 pc packs of screws.
They sent a duplicate of the original order plus the additional screws all for free including USPS priority mail. Everything arrived within two days.
I don't think I've ever dealt with a more responsive company.
I 've been buy from Mcmaster for years and have been very pleased. However, they sell many of the small screws. nuts and washers in min. quantities of 50 and more typically 100 pcs.
Albanycountyfasteners sells almost everything in quantities ranging from one piece, 25, 100, 250 or 1,000. Their shipping costs are pretty low and orders over $25 ship free.
I don't build a lot of things requiring small screws so I like the ability to buy very small quantities.
Albanycountyfasteners sells almost everything in quantities ranging from one piece, 25, 100, 250 or 1,000. Their shipping costs are pretty low and orders over $25 ship free.
I don't build a lot of things requiring small screws so I like the ability to buy very small quantities.
Conductive greases
I wired my garage, tool shed and a pole light using overhead aluminum cables and connectors about 15 years ago. Everything works like the day I installed it.
Before completing the job, I was telling a, very good licensed electrician, friend about the job. He said I should work in a conductive anti-oxidant grease, with a wire brush, in the wire ends and apply it to the connector surfaces. He said this is a standard procedure even used by utility companies. He recommended IDEAL Noalox. I used it and have quite a bit left.
I'm considering using it on all screws going into the aluminum case panels. These screws will be for mounting the XLRs with conductive bodies. the AC entry module and various copper ground wires to the panels. I like the idea of having good, long lasting grounds. It's so easy and I have the stuff.
I'd appreciate any thoughts or recommendations of other products that might be more appropriate.
I wired my garage, tool shed and a pole light using overhead aluminum cables and connectors about 15 years ago. Everything works like the day I installed it.
Before completing the job, I was telling a, very good licensed electrician, friend about the job. He said I should work in a conductive anti-oxidant grease, with a wire brush, in the wire ends and apply it to the connector surfaces. He said this is a standard procedure even used by utility companies. He recommended IDEAL Noalox. I used it and have quite a bit left.
I'm considering using it on all screws going into the aluminum case panels. These screws will be for mounting the XLRs with conductive bodies. the AC entry module and various copper ground wires to the panels. I like the idea of having good, long lasting grounds. It's so easy and I have the stuff.
I'd appreciate any thoughts or recommendations of other products that might be more appropriate.
Neutrik xlr
The Neutrik XLRs I bought have a tab, next to pin1, connected to the XLR body. I think using a very short wire from pin1 to the tab will make a good setup due to a very short wire connection to ground. I'm actuallay stripping about two inches of the cable. The unbraided twisted shield wires will be long enough to go from the cable, to pin1, and then to the tab.
This will ground the body, tab and pin1 to the panel via the mounting screws.
When I connect the ground wire, of the AC entry module to the same panel, the XLR body and pin1 will be grounded. Am I missing something?
The Neutrik XLRs I bought have a tab, next to pin1, connected to the XLR body. I think using a very short wire from pin1 to the tab will make a good setup due to a very short wire connection to ground. I'm actuallay stripping about two inches of the cable. The unbraided twisted shield wires will be long enough to go from the cable, to pin1, and then to the tab.
This will ground the body, tab and pin1 to the panel via the mounting screws.
When I connect the ground wire, of the AC entry module to the same panel, the XLR body and pin1 will be grounded. Am I missing something?
Yes. I believe you got it right. I do not think you have missed anything.
Yep. The room plays a big role in the perceived sound quality.
Tom
connecting the XLR socket shell to pin 1 effectively makes the shell an enclosing RF attenuating tube.
If the shell can have many electrically conductive point contacts with the enclosing chassis then that completes the "enclosure" for best RF attenuation.
The only gap in your tube enclosure around the signal cores is that from the end of the folded back screen to the enclosure. Keep this gap as small as possible.
The tab is about 1/16 away from pin1 so the extra wire will be incredibly short. Thinking a little more about this, instead of soldering the twisted shield to the pin1 solder cup, i could squeeze the wire between the outer diameter of pin1 and the tab and solder it as one joint. Any thoughts or downsides to that scheme?
If your connection would fail without the goop then it is quite clear that you've chosen the wrong style of connection; however, if your connection didn't need the goop and you applied it merely to increase quality unnecessarily farther, then you did it right.