coax for interconnects [Archive] - The Art of Sound Forum

JohnG

01-10-2018, 05:43

I don't think the balanced cables regularly referred today are fancy, but good quality affordable cable , that can be purchased unterminated. The RCA plugs are more of the
exotic and some brands of these, do come with a above average cost.
I,ve tried Coax and Balanced Microphone Cable, Unshielded Silver and Unshielded Copper Ribbon.
The most appealing to me at present is the Unshielded Copper.

CageyH

01-10-2018, 09:09

It all depends on the cable in question, and how you make up the balanced cable.
There are so many variables that it is very much a suck it and see exercise, in my opinion.

karma67

01-10-2018, 11:40

It’s not a balanced cable, it interested me that so many people on the diy audio forum advocated the use of coax rather than mic or twisted pair types of cable for interconnects.

CageyH

01-10-2018, 13:04

No, a coax cable is not balanced. We agree. ;)
My point was it depends on how you make up a balanced cable into an interconnect.
The best type of cable to use is the one you like the sound of best.

If you have a noisy environment a coax may not the best.

Bigman80

01-10-2018, 13:08

"My point was it depends on how you make up a balanced cable into an interconnect.

The best type of cable to use is the one you like the sound of best.

If you have a noisy environment a coax may not the best."

Exactly.

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Svend N

01-10-2018, 13:57

ive just been reading up on interconnects,from what ive learnt the best cable for unbalanced use is coax.
does anyone use this or do we all go for fancy mic cable these days?
lets discuss :)

Jamie, I did some experimenting with various unbalanced DIY cables recently -- probably tried at least 6 different ones, incl. a couple commercially-made. If I recall, three of the lot were coax, the rest were twisted pair with shield. These were all used between cd player and preamp. To my ears the coax sounded worst in all cases -- thin and harsh, smaller soundstage...they were really holding back the capabilities of the source. All the twisted pair ones were noticeably better - fuller, rounder, warmer sound; bigger soundstage. I finally settled on a Gotham twisted pair cable as having the cleanest, smoothest sound (very sweet), but a Belden pair also sounded very good, perhaps slightly coarser sounding than the Gotham. I haven't tried a quad cable, and may do that over the winter just to satisfy my curiosity. Also haven't tried a roll-yer-own phono cable as yet, but I have some bulk Mogami in the bin that would do nicely for that.

Hope this helps. I can dig out some model nos. for you if you're really curious.

Cheers,
Svend

karma67

01-10-2018, 15:36

Jamie, I did some experimenting with various unbalanced DIY cables recently -- probably tried at least 6 different ones, incl. a couple commercially-made. If I recall, three of the lot were coax, the rest were twisted pair with shield. These were all used between cd player and preamp. To my ears the coax sounded worst in all cases -- thin and harsh, smaller soundstage...they were really holding back the capabilities of the source. All the twisted pair ones were noticeably better - fuller, rounder, warmer sound; bigger soundstage. I finally settled on a Gotham twisted pair cable as having the cleanest, smoothest sound (very sweet), but a Belden pair also sounded very good, perhaps slightly coarser sounding than the Gotham. I haven't tried a quad cable, and may do that over the winter just to satisfy my curiosity. Also haven't tried a roll-yer-own phono cable as yet, but I have some bulk Mogami in the bin that would do nicely for that.

Hope this helps. I can dig out some model nos. for you if you're really curious.

Cheers,
Svend

cheers svend,
ive heard good reports of Gotham cable.

struth

01-10-2018, 15:56

still got some gotham speaker cable somewhere.. was very good

Bigman80

01-10-2018, 16:34

cheers svend,
ive heard good reports of Gotham cable.I felt it had an over emphasised thick midrange. Certainly didn't float my boat. I know of plenty who's boat it does though.

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Stryder5

01-10-2018, 16:44

Is that what Batman uses?

Their prices are quite good, so no Robin you:lol:

Svend N

01-10-2018, 17:14

I felt it had an over emphasised thick midrange. Certainly didn't float my boat. I know of plenty who's boat it does though.

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Which version did you try Oliver? There are a number of different ones. I used GAC-2 V1 (p/n 10421) in the make-up, with Neutrik plugs, and I don't perceive any midrange bloat. I just find it a very clean, clear, neutral sounding cable. Could be (and likely is) system-dependent as to results, as many things like this can be. But to Jamie's original question, all the coax cables were noticeably inferior to the twisted-pair versions. There was a much bigger difference between coax vs. twisted-pair, than between different versions of twisted-pair. Things started getting pretty subtle in what I was hearing between, say, a Belden vs. Mogami vs. Gotham twisted pair.

Bigman80

01-10-2018, 17:25

Which version did you try Oliver? There are a number of different ones. I used GAC-2 V1 (p/n 10421) in the make-up, with Neutrik plugs, and I don't perceive any midrange bloat. I just find it a very clean, clear, neutral sounding cable. Could be (and likely is) system-dependent as to results, as many things like this can be. But to Jamie's original question, all the coax cables were noticeably inferior to the twisted-pair versions. There was a much bigger difference between coax vs. twisted-pair, than between different versions of twisted-pair. Things started getting pretty subtle in what I was hearing between, say, a Belden vs. Mogami vs. Gotham twisted pair.I tried GAC-2. Gave it over 100hrs but I just didn't like it. That doesn't mean it isn't great in your system just that when I tried it I didn't like it.

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CageyH

01-10-2018, 17:29

Their prices are quite good, so no Robin you:lol:

There is always a Joker.

Bigman80

01-10-2018, 17:31

There is always a Joker.They are usually the "Bain" of our existence

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Svend N

01-10-2018, 17:50

I tried GAC-2. Gave it over 100hrs but I just didn't like it. That doesn't mean it isn't great in your system just that when I tried it I didn't like it.

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Yeah, I hear you. In my system, it's the best I've tried. I know you've been rolling a lot of cables lately, some from pretty hard-to-find bulk stock, so you have a lot more experience and more builds to compare. For me, I decided for reasons of sanity that the Gotham was good enough and that I could happily live with it. Otherwise I'd go nutso trying to find cable nirvana. My system has other more important things that need attention and tweaking.

Bigman80

01-10-2018, 17:52

No doubt mate and that's all there is too it. If you like what it does, fantastic result. It doesn't matter much what anyone thinks, just enjoy what you've found and fair play building some cables and doing your own testing.
Yeah, I hear you. In my system, it's the best I've tried. I know you've been rolling a lot of cables lately, some from pretty hard-to-find bulk stock, so you have a lot more experience and more builds to compare. For me, I decided for reasons of sanity that the Gotham was good enough and that I could happily live with it. Otherwise I'd go nutso trying to find cable nirvana. My system has other more important things that need attention and tweaking.

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Svend N

01-10-2018, 18:01

No doubt mate and that's all there is too it. If you like what it does, fantastic result. It doesn't matter much what anyone thinks, just enjoy what you've found and fair play building some cables and doing your own testing.

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Good one, Oliver. Well said. BTW, at some point I will go about a phono cable build and will post here for some advice...winter project...still decent-enough weather here to keep me out of the basement workshop for a while. :)

Barry

01-10-2018, 18:12

There's more than one version of Gotham GAC-2. And there is GAC-3 and GAC-4 to consider as well.

Svend N

01-10-2018, 18:20

There's more than one version of Gotham GAC-2. And there is GAC-3 and GAC-4 to consider as well.

Quite correct Barry. The differences seem to be in the shielding and insulation. As mentioned, I used GAC-2 V1, p/n 10421: https://gothamcables.com/en/gothamcables/balancedanalog/10421gac2v1

karma67

02-10-2018, 14:41

Svend N

02-10-2018, 15:48

Good one Jamie. It will be interesting to hear your impressions of the two.

The twisted pair one is curious, in that it seems that one conductor has 7 x 0.1mm strands, and the second has 21 x 0.1mm strands. I've not seen that before. You'll have to pay attention to which is supply and which is return. And how do you plan to solder the shield? Most layups have the shield joined with the return conductor at the source end, and the shield is cut short (not joined) at the preamp/amp end. At least that's how I learned to do it; I think others here do the same(?)

Best of luck with the project.

Svend

karma67

02-10-2018, 16:03

cheers svend,
i went with that one because j7 uses it for tonearm cable,i had my zeta rewired a while back and always like the sound.
yep i'll use the shield connected at the source end only.

Svend N

02-10-2018, 16:21

Good one Jamie. I'll have to keep that stuff in mind for when I build up a phono cable. I was thinking of using some Mogami 2534 that I have on hand, but am open to other options. Thanks for that!

Svend

Bigman80

02-10-2018, 16:56

well ive just bought these 2 types of cable to have a play.
https://www.ebay.co.uk/itm/Van-Damme-Silver-Series-Session-Grade-Instrument-Cable-Low-Cap-55-by-metre-/131606957718?hash=item1ea462ce96

and this,

https://www.ebay.co.uk/itm/Van-Damme-Pro-Grade-Classic-XKE-Pro-patch-Cable-Metre-Colour-Choice-/131415213540?var=&hash=item644b5e208eHad both.

The LoCap stuff is the only Van Damme cable I've ever liked. It's got a lot of quality, unfortunately I found the top end a bit too hot for my taste. It's also a right bitch to get in any RCAs other than the MSAUDIO ones or those of similar design for large diameter cables.

The other one I've used as Interconnects and tonearm cable. Does a reasonable job but the bass was flabby and under controlled.

Obviously these are just my experiences and yours may differ. Fair play for having a go

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karma67

02-10-2018, 17:03

The other one I've used as Interconnects and tonearm cable. Does a reasonable job but the bass was flabby and under controlled.

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cheers, it's interesting that a cable can totally change the characteristics of a speaker driver.so many variables,did you try to compensate with speaker position ?

Bigman80

02-10-2018, 17:14

cheers, it's interesting that a cable can totally change the characteristics of a speaker driver.so many variables,did you try to compensate with speaker position ?No mate, no speaker shuffling. Whatever I use has to be right where the speakers are.

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mikmas

02-10-2018, 17:31

ive just been reading up on interconnects,from what ive learnt the best cable for unbalanced use is coax.

Just out of interest - what do you mean by 'coax' ?
I automatically think of aerial/cable TV connector lead - which seems like an impossible wrestle with any RCA connector - or alternatively the 75ohm stuff that's used for SPDIF connection (which I have tried as analogue cable)

Svend N

02-10-2018, 18:11

Mike, coax is a single central conductor surrounded by insulation and then a shield of some kind (either spiral wrap or braided). The centre conductor carries the signal and is soldered to the centre pin of the RCA plug. The shield is unwrapped for a short length, then gathered together and twisted to form a single "rope" of wire; this is then soldered to the negative shell of the RCA and serves as the return conductor. So you are quite right, the cable is the same basic layup as that for TV lead.

Hope this makes sense...

Svend

mikmas

02-10-2018, 18:22

JohnG

02-10-2018, 18:26

I've used the Van Damme Low Cap, and liked what it was offering, it is in with my use again cable pile and the Ecosse Cable it replaced is now shelved.

Svend N

02-10-2018, 18:53

Stryder5

02-10-2018, 19:53

Thanks Svend - :)

I understand how a conventional audio lead is constructed (and have also made many), what I am a bit confused about is the use of the term 'coax' in that context.
I have always understood coax to be a particular kind of arrangement with specific requirements in relation to construction of the insulation layer surrounding the inner core, with 'ordinary' audio cable as such not falling into that category.

I am no EE though ... and perhaps that's what's needed to clarify the distinction.

I'm no EE but I believe you're correct in that there are specific requirements for "coax", that being that the coax must maintain a specific impedance. Care must be taken to ensure that conductors and dialectric do not effect this impedance.

Coax is constructed with a single conductor and an outer shield ( normally a braid with maybe a foil or film outer). Hence the name coaxial construction.

For example 50 Ohm and 75 Ohm are typical standards, although there are others.

Hope I'm not teaching you to suck eggs.

Gary

mikmas

02-10-2018, 19:58

Hope I'm not teaching you to suck eggs.

Gary

Not at all Gary - thanks for that, seems to confirm what I was thought I knew and why this topic confuses me a bit ;)

karma67

02-10-2018, 20:06

Not at all Gary - thanks for that, seems to confirm what I was thought I knew and why this topic confuses me a bit ;)

Do what I did a google search, coax for interconnect and then like me you’ll be even more confused lol

Stryder5

02-10-2018, 20:16

Not at all Gary - thanks for that, seems to confirm what I was thought I knew and why this topic confuses me a bit ;)

The answers to your OP did wander around a bit......:scratch:

struth

02-10-2018, 20:27

Thanks Svend - :)

I understand how a conventional audio lead is constructed (and have also made many), what I am a bit confused about is the use of the term 'coax' in that context.
I have always understood coax to be a particular kind of arrangement with specific requirements in relation to construction of the insulation layer surrounding the inner core, with 'ordinary' audio cable as such not falling into that category.

I am no EE though ... and perhaps that's what's needed to clarify the distinction.

Yup, its a mix between the dialetric and the inner and outer cores that make the coax, and the dialetric size for 50 or 75 ohm; plus the connectors have to be the correct ones too. a proper bnc for 75ohm doesnt have dialetric. Getting the capacitance wrong can chop the square wave of a digital signal for instance.
an rca version is usually not exactly 75ohm due to the plug although canare plugs are 75ohm
http://www.canare.com/ProductItemContentImages/1330.jpg

mikmas

02-10-2018, 23:28

Do what I did a google search, coax for interconnect and then like me you’ll be even more confused lol

You ain't wrong on that one - right hornet's nest on some forums :rolleyes:

mikmas

02-10-2018, 23:39

Yup, its a mix between the dialetric and the inner and outer cores that make the coax, and the dialetric size for 50 or 75 ohm; plus the connectors have to be the correct ones too. a proper bnc for 75ohm doesnt have dialetric. Getting the capacitance wrong can chop the square wave of a digital signal for instance.

Good stuff Grant ... roughly what I thought, but then some ....

I have used pairs of 75ohm leads in the past for analogue connectors (out of curiosity) and to be honest found no difference to speak of.
The reverse though was more destructive - using a typical RCA analogue lead as an SPDIF carrier did have a clear effect on the sound .. noticeably brittle and harsh.

Have also done some limited experimentation with mic cable for unbalanced (and pseudo-balanced) ICs but found no real advantage as yet over the more conventional Van Damme/Neutrik combo.

Might give some Mogami 2549 a whirl ... have some of the famous Star plugs on their way from the orient at the mo' so will see when they eventually land ;)

Barry

02-10-2018, 23:48

Yup, its a mix between the dialetric and the inner and outer cores that make the coax, and the dialetric size for 50 or 75 ohm; plus the connectors have to be the correct ones too. a proper bnc for 75ohm doesnt have dialetric. Getting the capacitance wrong can chop the square wave of a digital signal for instance.
an rca version is usually not exactly 75ohm due to the plug although canare plugs are 75ohm
http://www.canare.com/ProductItemContentImages/1330.jpg

It is impossible for an RCA phono connector to have a characteristic impedance of any more than ~57 Ohm, and in practice is more likely to be between 30 - 40 Ohm, depending on the dielectric used to support the centre pin.

Canare plugs cease to be 75 Ohm once they are mated with a conventional phono socket.

struth

03-10-2018, 00:04

It is impossible for an RCA phono connector to have a characteristic impedance of any more than ~57 Ohm, and in practice is more likely to be between 30 - 40 Ohm, depending on the dielectric used to support the centre pin.

Canare plugs cease to be 75 Ohm once they are mated with a conventional phono socket.

thought thats what i said:)

mikmas

03-10-2018, 00:07

It is impossible for an RCA phono connector to have a characteristic impedance of any more than ~57 Ohm, and in practice is more likely to be between 30 - 40 Ohm, depending on the dielectric used to support the centre pin.
Canare plugs cease to be 75 Ohm once they are mated with a conventional phono socket.

So presumably BNC connectors/sockets are capable of maintaining the 75 ohm integrity?

struth

03-10-2018, 00:10

Good stuff Grant ... roughly what I thought, but then some ....

I have used pairs of 75ohm leads in the past for analogue connectors (out of curiosity) and to be honest found no difference to speak of.
The reverse though was more destructive - using a typical RCA analogue lead as an SPDIF carrier did have a clear effect on the sound .. noticeably brittle and harsh.

Have also done some limited experimentation with mic cable for unbalanced (and pseudo-balanced) ICs but found no real advantage as yet over the more conventional Van Damme/Neutrik combo.

Might give some Mogami 2549 a whirl ... have some of the famous Star plugs on their way from the orient at the mo' so will see when they eventually land ;)

Ive used the too and they are fine, but as you say, not the other way round. Think the only real way is via bnc plugs. I usually prefer to use usb or fibre.

Barry

03-10-2018, 00:11

So presumably BNC connectors/sockets are capable of maintaining the 75 ohm integrity?

Yes, BNC connectors are constant impedance designs. They come in two impedances: 50 Ohm and 75 Ohm. The 50 Ohm versions have a thicker centre pin.

mikmas

03-10-2018, 00:16

Ive used the too and they are fine, but as you say, not the other way round. Think the only real way is via bnc plugs. I usually prefer to use usb or fibre.

Yup - usually use USB or optical for MAC-DAC or RPi-DAC connections ... but actually currently running Firewire 800 into 400 (which is a very different kettle of worms ...:lol: )

struth

03-10-2018, 00:17

this was how we were told to identify them but could be other versions

http://www.wecusurveillance.com/files/891125/uploaded/507hohm.jpg

struth

03-10-2018, 00:19

Yup - usually use USB or optical for MAC-DAC or RPi-DAC connections ... but actually currently running Firewire 800 into 400 (which is a very different kettle of worms ...:lol: )

I have a firewire cable but never had the opportunity to use it. not found anything that has one bar my laptop :doh:

tlscapital

04-10-2018, 14:28

Well I was given stil unwrapped an 'audio' oxygen free coper cable that found it's way with the unused gear 'place' in the basement. The day I decided to re-cable my original SME one in not such good shape anymore, I went and decided to try that 'audio' cable and clipped out both RCAs at one end and solder that cable to the original 4 pin connectors bar of the SME tonearm base. Instantly got better sound definition; better focus and clarity. Before in comparison muffled and muddy. The RCAs swap alone are not solely responsible for that I understand. The lower capacitance of this coax 'audio' cable is also a factor there. Now I have never tried pricier phono cables, but I am not necessarily convinced upfront them to be an universal "upgrade". On some set-up yes and for some ears also...

tlscapital

05-10-2018, 17:39

Careful - you'll get people paranoid wondering if their cables contain halogen. :lol:

Thanks for pointing out my tipping mistake. Now revised... :)

Lawrence001

05-10-2018, 17:57

Just out of interest, ohms measure resistance (or impedance), what 2 points on a 75ohm cable, or connector, is the value measured between?

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The Masked Avenger

28-10-2018, 14:07

It’s not a balanced cable, it interested me that so many people on the diy audio forum advocated the use of coax rather than mic or twisted pair types of cable for interconnects.There is, of course, the pairing in a shield commonly known as a "balanced co-axial".

Firebottle

28-10-2018, 14:36

Just out of interest, ohms measure resistance (or impedance), what 2 points on a 75ohm cable, or connector, is the value measured between?

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The impedance of a 75 or 50 ohm cable can only be measured at radio frequencies, it does not equate to a resistance that can be measured with a multimeter or at audio frequencies.
It is also a 'distributed' impedance, between the centre conductor and the outer shield. The impedance will measure the same wherever it is measured along the cable, this is the whole point of a constant impedance cable so that RF signals don't meet any discontinuity in impedance.

Discontinuities will cause mismatch and reflections resulting in a high Voltage Standing Wave Ratio (VSWR). In extreme cases this high VSWR can cause damage to RF equipment.

goraman

01-11-2018, 20:58

Firebottle

02-11-2018, 07:44

Ever played with 10GHz stuff Jeff?
I used to do amateur TV up to 10.5GHz, built a repeater station, converted LNBs to transmitters etc.

Light Dependant Resistor

02-11-2018, 08:07

The impedance of a 75 or 50 ohm cable can only be measured at radio frequencies, it does not equate to a resistance that can be measured with a multimeter or at audio frequencies.
It is also a 'distributed' impedance, between the centre conductor and the outer shield. The impedance will measure the same wherever it is measured along the cable, this is the whole point of a constant impedance cable so that RF signals don't meet any discontinuity in impedance.

Discontinuities will cause mismatch and reflections resulting in a high Voltage Standing Wave Ratio (VSWR). In extreme cases this high VSWR can cause damage to RF equipment.

However , https://theartofsound.net/forum/showthread.php?34105-Coax-cable-50-ohm-for-audio-interconnects-and-speaker-hookup
Cyril Batemans article indicates speaker cables do comply with established transmission line behavior.

Regarding measuring - rather than cable impedance that is indeed difficult with a multimeter, I recall measuring what appeared as actual antenna impedance with a multimeter, I recall measuring close to 30 ohms of a monopole antenna atop a roof, using nothing more than a multimeter.

Barry

02-11-2018, 15:08

The concept of characteristic impedance and the treatment of cables as transmission lines only applies when the length of the cable is much greater than the wavelength of the signal/(2*pi). For most insulating materials the signal propagation velocity in the cable will be ~ 2 108ms-1. Thus at 20kHz, the cables would have to be longer than 10km for transmission line theory to apply.

It is impossible to measure the characteristic impedance of a cable with a simple multimeter.

Anyway we are not interested in matching amplifier to speaker, in the sense of desiring maximum power transfer as one does at VHF and microwave frequencies. Amplifiers are effectively voltage sources and have a very low source impedance. It is the ratio of source impedance to speaker load impedance that allows the amplifier to dampen the back emf generated by the speaker. (i.e. to prevent the 'tail wagging the dog'). The loop resistance of the speaker cables appears in series with the amplifier's output impedance, so need to be kept as low as possible so as not to degrade the damping factor.

Light Dependant Resistor

02-11-2018, 19:28

Hi Barry
Did you take a look at the Cyril Bateman article ?
http://web.archive.org/web/20091027010126/http://uk.geocities.com/cyrilb2@btinternet.com/downloads_5.html

"Many writers claim that at audible frequencies, our loudspeaker cable cannot act as a transmission line
because it is much too “short”. This view became established some years ago following the widely
published and much copied paper by R. A. Greiner, which simply stated some facts about cable lengths
etc., without going into any form of proof. Sadly his basic calculations/assumptions were some 600% in
error, mostly due to the slowing down affect of the cable’s insulation. He also assumed reflections would
only occur when a cable was one wavelength long, when in fact the most troublesome reflections occur
at odd one quarter wavelengths and with cables very much shorter than one quarter wavelength long."

And we are all agreeing repeated a few times that a multimeter cannot measure cable impedance,

however as I found when loaded by some types of antenna, a resistance measurement approximating
the expected characteristic impedance of that antenna ( vs cable) appears, using nothing more than
a multimeter. Multimeter was a Fluke 12. As I say I was atop a roof, but noted it at the time some 30 years ago.
antenna was a monopole, where just over 30 ohms was expected.

Alan D

02-11-2018, 19:56

Ever played with 10GHz stuff Jeff?
I used to do amateur TV up to 10.5GHz, built a repeater station, converted LNBs to transmitters etc.

I built the Practical Wireless 10GHz Wideband transceiver around 1986

http://www.microwave-museum.org/exhibits/mwm-003.htm

73 de G4PSU

Barry

02-11-2018, 20:31

I have read many of Cyril Bateman's articles in Wireless World magazine (well actually Wireless World and Electronics magazine), when it was editorial policy to allow more speculative articles that questioned established thinking. Some of these were thought-provoking, such as Ivor Catt's maverick questioning of the need for displacement current to complete Maxwell's equations, and the motion of charge on the electrodes of a capacitor as it is charged. So this lateral and open thinking was indeed refreshing, but it also permitted some 'voodoo science' to be promulgated. Sadly a few articles on the propagation of audio signals in cables fell into this category.

Much of Bateman's work is well done (the measurements especially), but his theoretical thinking is muddled, and his maths incorrect; as pointed out in subsequent letters to the magazine. His work on the possibility that speaker cables can act as very inefficient antennae to RF is interesting, and the idea that the use of screened cable to counter this effect may have influenced his thinking that speaker cables should be thought of as transmission lines at audio frequencies.

But to show that transmission line theory can be applied at audio frequencies, it was noted in the '30s that some mains distribution networks were being overloaded but with no obvious cause. It was eventually found that some unterminated branches of the network were approaching a quarter wavelength long (which at 50Hz, is approximately 75km long), and the open circuit at the end was being transformed to a very low load impedance at the junction.

goraman

03-11-2018, 05:06

I built the Practical Wireless 10GHz Wideband transceiver around 1986

http://www.microwave-museum.org/exhibits/mwm-003.htm

73 de G4PSU

No, 10 ghz. just scares me. Was that you on the cover?
Thats crazy 86 to 89 is when I was playing with gobs of RF near 30MHZ. You where at the very early years of Amateur microwave, I remember all my friends talking about it in those days.
Microwave would be very line of sight, with such a tiny wave form a leaf would deflect the signal.
I did help run hard line (very big coax stiff as hell ) for a UHF repeater with a friend of mine. That stuff had very low absorption.
It would matter even more at 10 ghz, what coax did you need for that?
I no longer do any Amateur Radio but my Call was KC6UJS .
I have been exposed to so much RF radiation Conner should have been born a cyclops with an extra arm. At one point I had a 5/8 wave copper dipole 35 ft. on a mast welded and reenforcement on top a 20 ft. aluminum camp trailer,inside was my station.( I was inside the ground plane)When I keyed down,there was enough RF to light a standard light bulb! My transmitter held 20 Ratheon 6LQ6 beam tubes! 6 huge iron core transformers and took 2 people to lift it.
2000 watts RMS into that home made copper dipole was no problem and on single side band there was no place I could not be heard when conditions where right. At 27,910 it would swing to nearly 2,300 on AM or FM with fresh tubes.
SSB was just off the meter. That was the sweet spot for that ariel. It was fun then but not very smart.