The topic was what properties can affect sound, with connectors. I don't see how the sound of the connector would affect the "sound" passing through the connector. But by all means if you have a secret tuning fork method to determine connector quality, please share 😀
Scott --
No they didnt. However ----- we always used better materials and much better connectors. Never consumer grade (if there is such a thing). The freqs there were so much higher that small imperfections could cause vswr ripple and atten. The handling and care and cleaning of the precision connectors and cables were observed.
I was able to verify the Gen Radio slotted line as having vswr of 1.001 at 1Ghz and .002 at 2Ghz. but that precision was in a secondary standards lab and with high precision gear , attenuators, cable, source, loads and their connectors and hand plotted on Smith chart... all stuff i dont know how to do any more.
THx-RNMarsh
No they didnt. However ----- we always used better materials and much better connectors. Never consumer grade (if there is such a thing). The freqs there were so much higher that small imperfections could cause vswr ripple and atten. The handling and care and cleaning of the precision connectors and cables were observed.
I was able to verify the Gen Radio slotted line as having vswr of 1.001 at 1Ghz and .002 at 2Ghz. but that precision was in a secondary standards lab and with high precision gear , attenuators, cable, source, loads and their connectors and hand plotted on Smith chart... all stuff i dont know how to do any more.
THx-RNMarsh
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Not my experience, Pomona stock cables right off the rack never saw anyone clean a BNC. I mean how do you get inside and clean a BNC? Spraying anything on a Keithley triax would be frowned upon.
Well thats my experience and trained by HP at their training center on precision measurements with precision gear and that included the connectors.
I said precision connectors and cables, only. That does not include RCA or XLR or banana etc.
You can pressure spray on Kiethley triax BNC connector as long as it leaves no residue. And Q-tips in alchohol on some others.
Precision as in APC-7. type N mil spc. I dont know that the quality and precision exists in any pomona connector. But As I have said before, even the BNC breaks thru oxide build up with every insertion and twist of the bayonet connector. Center pin of gold (no oxide).
it all depends - for audio - on the male/female quality and materials, type of materials and if air tight etc etc. No reason to assume the chassis mounted are not different base metal from the cord connector, also.
Lets not discount the means of wire attachment to the center pin. In consumer rca they may be soldered or a poor mechanical contact. And poor soldering can lead to one end different from the other end. A lot of the soldered parts I have seen for consumer cable are what we could classify as a cold solder joint or near that. not a mil spec joint. The BNC cable/connector combo using proper tooling which will crimp the wire in an air tight connection with 360 degree crimp... copper wire to gold pin. Very reliable and contact stable over time. Same with 360 degree shield and how it contacts the BNC 360 degree contact..
so I buy my cables with mil spec assembly and mil spec adapters. [Not from Walmart.]
-RNM
I said precision connectors and cables, only. That does not include RCA or XLR or banana etc.
You can pressure spray on Kiethley triax BNC connector as long as it leaves no residue. And Q-tips in alchohol on some others.
Precision as in APC-7. type N mil spc. I dont know that the quality and precision exists in any pomona connector. But As I have said before, even the BNC breaks thru oxide build up with every insertion and twist of the bayonet connector. Center pin of gold (no oxide).
it all depends - for audio - on the male/female quality and materials, type of materials and if air tight etc etc. No reason to assume the chassis mounted are not different base metal from the cord connector, also.
Lets not discount the means of wire attachment to the center pin. In consumer rca they may be soldered or a poor mechanical contact. And poor soldering can lead to one end different from the other end. A lot of the soldered parts I have seen for consumer cable are what we could classify as a cold solder joint or near that. not a mil spec joint. The BNC cable/connector combo using proper tooling which will crimp the wire in an air tight connection with 360 degree crimp... copper wire to gold pin. Very reliable and contact stable over time. Same with 360 degree shield and how it contacts the BNC 360 degree contact..
so I buy my cables with mil spec assembly and mil spec adapters. [Not from Walmart.]
-RNM
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Actually, connector care is very important. It is so easy to have someone damage a connector or mating jack!
I have a test jig that uses an APC7 connector, but no component stages for it. That connector is actually really interesting.
-Chris
I have a test jig that uses an APC7 connector, but no component stages for it. That connector is actually really interesting.
-Chris
http://microwave.unipv.it/pages/microwave_measurements/appunti/01b_MM_connectors.pdf
Page 20 of this made me laugh. The number of Engineers who got shouted at for putting an APC-7 on their desk mating face down. A special humilation in front of the office for those who used to slide them around like that whilst idly mulling something.
Page 20 of this made me laugh. The number of Engineers who got shouted at for putting an APC-7 on their desk mating face down. A special humilation in front of the office for those who used to slide them around like that whilst idly mulling something.
What's with air tight? Isn't it enough that connector contact area is equal or greater than conductor area? In most cases it will be many times greater.
Getting DC to daylight performance is a little trickier than audio. Also some connectors (like the fischer ones) are made to work in hostile environments where corrosion may occur. And they make a lovely 'plop' when unmated. JC did use them on the early levinson stuff IIRC.
Do you really stick your fingers in your ears when you get an answer you don't like? 😉
Thing is, not screwing up APCs and other$200+ a pop connectors or kinking the $5000 1m calibrated coax or remembering to replace sacrificial adaptors after x cylces is all part of induction for any starter at a lab that uses that gear.
If the most exotic connector in the lab is a BNC things are a little more lax. But these days 4GHz is considered baseband! Never seen anyone clean a BNC. You chuck it in the bin and grab another.
If the most exotic connector in the lab is a BNC things are a little more lax. But these days 4GHz is considered baseband! Never seen anyone clean a BNC. You chuck it in the bin and grab another.
Everything just happens too fast for me these days! I remember being fascinated by the microwave gear in the PO tower during my BT apprenticeship
Even testing CAT5 cables requires replacing and retaining the test cable used between the instrument and cables under test after a fixed number if tests, often 100.
yes. and that center pin was field replacable because of any scratches on it or wear affected the measurement to the extent that it wouldnt meet spec any more. One thing that was pointed out and maybe useful here -- is to never rotate the whole connector... press the connector to its mate and only turn the outer body. This prevents wear on the center pin whose dimensions and quality must be like new to meet spec.
if you want a high quality mil spec made cable assembly buy from a company that i use https://www.pasternack.com/
Thx-RNMarsh
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That was probably proper hairy chested waveguide. Nice factoid. The post office (then later BT) had maps showing the Fresnel zones around the tower and would try and block planning for things that might bend the beams.
Liking or not liking does not even enter my mind, it's all nonsense these days. Nyuk, nyuk.
Derfy,
I know you are lurking about, so could you explain to the heathens how charge moves through a conductor?
I know you are lurking about, so could you explain to the heathens how charge moves through a conductor?
Haphazardly and only in net aggregate when we're talking in bulk (e.g. cables, even non-extreme skin effect). Only when you move down to very very VERY low dimensions do you start talking about any one electron.
Otherwise it's a lot of bumping around of weakly associated electrons (little bit of heat needed to free them) getting ever so slightly nudged in a direction. Or quite nudged in the cases where electromigration is a big deal. That's really high current densities, though.
Otherwise it's a lot of bumping around of weakly associated electrons (little bit of heat needed to free them) getting ever so slightly nudged in a direction. Or quite nudged in the cases where electromigration is a big deal. That's really high current densities, though.
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