20 plus talking range back in the day now cant talk across town...why

[Retroradio]

Odd question of the day.
Okay to clarify that. Back in the 70s’s/80’s using stock radios 20 miles plus was easy.
Now there’s a bunch of us in a small town here (no high rises etc) that from one end of town to the other drop manage to do a whopping 4-6 “S”units. All are running Anton99 or 5/8s 30ft...ish in the air.
Different radios, mic’s, antennas have been tried etc..
All having played radio for many years have discussed this and the conclusion was......drum roll.....nobody has a clue...lol
Anyone have any ideas.

 

[GrayJeep]

Assuming the antennas, radios and power are the same........

The RF noise level in the environment has gone up significantly due to all the computers, phones, wifi nodes, and the switching power supplies to run them. Phone and wifi are not on the same frequencies as CB but they can put out spurious emissions. Add 10,000 spurious emissions together and the noise level has gone up. Switching power supplies are more efficient than linear supplies but the switching going on in them creates a huge amount of broad spectrum noise. So noise level is my best estimate.

 

[Retroradio]

GrayJeep
All good and valid points. What I forgot to mention in my original post is that we have .5 to 3 “S” units of noise on a bad day. We have eliminated that possibility as it was our first thought. Thanks for the input though!

 

[russbrill]

Odd question of the day.
Okay to clarify that. Back in the 70s’s/80’s using stock radios 20 miles plus was easy.
Now there’s a bunch of us in a small town here (no high rises etc) that from one end of town to the other drop manage to do a whopping 4-6 “S”units. All are running Anton99 or 5/8s 30ft...ish in the air.
Different radios, mic’s, antennas have been tried etc..
All having played radio for many years have discussed this and the conclusion was......drum roll.....nobody has a clue...lol
Anyone have any ideas.

20 Miles in the old days??? Yes and No.. Let me explain. It depends on the location and elevation of each station, it wasn't uncommon to communicate with George Town in the foothills from Sacramento back in the good old days. Keep in mind George Town is at a 2600ft elevation. Try talking from Sacramento to Stockton (Low elevation station to low elevation station) with a legal setup, it ain't happening..

And of course, antennas/feed lines play a major role in station performance. A properly installed (SWR 1.5 or less) 5/8 wave ground plane with RG-213 coax mounted at least 10ft above your roof should have 5 to 10 miles of range. Remember, any guy wires near the antenna should be broken up with insulators... Stay away from Fiberglass dummy loads claiming to be antennas

 

[mrweather]

All else being equal, a couple of 11m yagi antennas (3-4 elements) pointed at each other should be able to achieve that range.

 

[a417]

GrayJeep
All good and valid points. What I forgot to mention in my original post is that we have .5 to 3 “S” units of noise on a bad day. We have eliminated that possibility as it was our first thought. Thanks for the input though!

Was this done on the radios in question or a spectrum analyzer?

 

[Retroradio]

A417, done with the radios not a spectrum analyzer mostly but has been done with both.

Russbrill, In the old days it was all over Toronto and surrounding area with stock radios. Various altitudes, buildings etc. Your point is valid however we are talking no mountains, hills etc.. in this town that you can drive across in 15 minutes including traffic lights...
The groups is running a mix of antennas and all are not Fiberglass dummy loads and the average SWR is below 1.5-1. Sets up with an anylzer and not an internal meter.
We are not getting an effective range like the days gone past hence my question. Having been playing radio for over 4 decades this is the first time I have run into this.

 

[a417]

A417, done with the radios not a spectrum analyzer mostly but has been done with both.

I'm sorry, but this reads as contradictory to me.

 

[russbrill]

A417, done with the radios not a spectrum analyzer mostly but has been done with both.

Russbrill, In the old days it was all over Toronto and surrounding area with stock radios. Various altitudes, buildings etc. Your point is valid however we are talking no mountains, hills etc.. in this town that you can drive across in 15 minutes including traffic lights...
The groups is running a mix of antennas and all are not Fiberglass dummy loads and the average SWR is below 1.5-1. Sets up with an anylzer and not an internal meter.
We are not getting an effective range like the days gone past hence my question. Having been playing radio for over 4 decades this is the first time I have run into this.

Noise is a real problem everywhere... I have attached an interesting article by another old time radio guy, I hope you find it as informative as I did..

 

[wtp]

and how many are using the original coax...??

 

[K6EEN]

We are not getting an effective range like the days gone past hence my question. Having been playing radio for over 4 decades this is the first time I have run into this.

The crystal filters or channel selectivity filters in modern production CB radios i.e. radios at the $100 to $200 price point (2020 dollars) are a far cry from what was put in the 1970s era radios at a $300 or $500 price point (1975 dollars). You'll find disucssions and videos of comparisons and replacement all over the 'net. Here's an example of a President AM receive fix, and SSB receive comparison.

Fixing deaf President CB radio by replacement a crystal filter CQ S455HT

Why your modern SSB side band CB receive is noisy.

 

[p1879]

Same issue here but looks like component failure; the cranial inter-aural amplifier has been de-sensed from high-power audio frequency signals.

 

[Retroradio]

I'm sorry, but this reads as contradictory to me.

Most were done with the radio meters but some were done with a spectrum analyzer. Its pretty simple here as I have virtually no noise.

 

[Retroradio]

and how many are using the original coax...??

Most of the locals are running new coax. I am also running new coax And dont have an RFI issue on receive.

 

[Retroradio]

Noise is a real problem everywhere... I have attached an interesting article by another old time radio guy, I hope you find it as informative as I did..

Agreed, man made noise is an issue.
I cant get the article to open.

 

[KEWB-N1EXA]

Odd question of the day.
Okay to clarify that. Back in the 70s’s/80’s using stock radios 20 miles plus was easy.
Now there’s a bunch of us in a small town here (no high rises etc) that from one end of town to the other drop manage to do a whopping 4-6 “S”units. All are running Anton99 or 5/8s 30ft...ish in the air.
Different radios, mic’s, antennas have been tried etc..
All having played radio for many years have discussed this and the conclusion was......drum roll.....nobody has a clue...lol
Anyone have any ideas.

From KQX9282
Around 1975 when the sun spot activity was low and the band was clean of noise I could go 15-20 miles 4 watts on AM.
By 1980 the solar noise was so bad you couldn't talk more than a few miles.
I'm using currently a Cobra 148 and around mid day can talk 12 miles on ssb to another base station. But Id say late afternoon the noise level rises.
So allot has to do with E and F layer Propagation , The Noise Floor and the time of year throw in that were on the rise of the next
sun spot activity and rising slowly for the next few years.
I usually turn on the cb and go to CH 38 SSB and see if the atmosphere is fired up for activity. some time the noise floor is so bad you just shut it off.

Current sunspot cycle activity - Solar Cycle 25; Space weather, solar storm and geomagnetic conditions, and radio propagation forecasts

Pete N1EXA

 

[chief21]

We are not getting an effective range like the days gone past hence my question.

Assuming all other variables remain constant, the two biggest changes are probably the overall increase in the noise floor and the sunspot cycle. Remember that we just recently passed the solar minimum. Propagation should be much better in another year or two, until the DX becomes overwhelming.

 

[Retroradio]

Cycle makes sense as I like many have been through it. We used to do the 20ish miles and that stopped when the noise floor got so bad you couldn’t talk across the street. I agree on the noise floor/propagation And that does seem the most logical explanation and will go with that.
However, right now we cant even get 12 miles SSB local, AM is limited to town use, and right now here the band is clear of noise hence my confusion.

 

[KEWB-N1EXA]

Cycle makes sense as I like many have been through it. We used to do the 20ish miles and that stopped when the noise floor got so bad you couldn’t talk across the street. I agree on the noise floor/propagation And that does seem the most logical explanation and will go with that.
However, right now we cant even get 12 miles SSB local, AM is limited to town use, and right now here the band is clear of noise hence my confusion.

I know allot of people reading this are going to scoff and say he's full of it but I was there . In 1975 the band was flat with no noise.
I had a Ray Jefferson cb805 which was a straight radio with PLL crystals.. No Processors or Modern Chip Radio and there is a difference.
Old CB radio that were Tube or Straight Transistor had a much cleaner receiver and were more sensitive. So with the CB805 and an Avanti
Astro Plane which is a bunch of stacked 1/4 waves in a sexy form to look space age you would get up in the morning and it was dead quiet
and you could talk 20 miles to another base or on Sunday morning id be in the Boat fishing and mom would call in and check on us and that
was 10 Miles over water so I remember those days.
Move ahead 45 + years later and everything is processor driven radios and pretty much lack luster antennas out there. Most Base stations
are not running 5/8 wave monsters nor do people run 1/4 wips on thier cars. I turn my 1990s cobra 148 on and there is at least 1-3 db noise on the floor to deal with then throw in Band Conditions. The times have changed the HF band goes with what the sun and the Atmoshere does with it and radios arent the same. Fire up a big old school Browning Golden Eagle or Tram D201 and you say wow this has a nice sound.

Pete N1EXA former KQX9282

 

[Retroradio]

KEWB-N1WXA, Well said.