On Tue, Oct 25, 2022 at 09:51 PM, Bob Dengler wrote:

At 10/25/2022 01:32 PM, you wrote:

My point is, where is the energy above 3Khz comming from? Unless it is background music or road noise. The audio
spectrum from the human voice isn't there.

You must not have a tongue or teeth; my sympathies.

No - Really.? There is little "need" of energy above 3khz for male voice inteligibility.? It goes a little higher to 4k for women.
If you want singing or screaming of little children, you might want to go higher.

The idea of getting AM broadcast to 6kc was to help music reproduction.
If the voice audio is well equalized for inteligibility, it's not a bad thing to have 50hz- 6khz but you won't likely hear anything
above 3000 and if anyone wants to do any bass boosting it will get old fast.

"Bass boosting"? No one has mentioned that; what does that have to do with this discussion?

A lot of people are doing wierd things like base boosting in order to get that "Barry White" DJ sound.? Or for Hi Fi SSB that actually was mentioned.

And there is no reason to pass the PL either.

Why not?

Added distortion of the PL tone originating at the mobile to be passed on to the transmitter?? Do you want a community repeater?

If someone really WANTS 6kc audio, it will have to be addressed throughout the chain, and keep an eye on the spectrum
analyzer.

Why? I'm sorry but this is borderline nonsense. Just what is to be "addressed throughout the chain"?

I was referring to the whole repeater chain as a system, including the user's transmitted signal to the repeater received signal and whatever processing to the
controller and whatever processing to the transmitter and whatever processing to the recovered audio at the user end.?? Because if you increase the modulating
frequency without either reducing the Dev or rolling off the modulating frequency, the occupied bandwidth will increase.? So you will need to do whatever
adjustments "throughout the chain" to insure you don't exceed the bandwidth limited by the coordinating body by looking at a narrow enough spectrum analyzer
to see what is happening at the transmitter output depending on the spectrum imposed at the modulator.? It is good to take a wholistic approach to the audio
quality because many errors "throughout the chain" may contribute to audio degradation at the users receiver.? Thank you for asking, if you need more detail
let me know.? In any case, I don't live anywhere near the border, so maybe you could explain "borderline nonsense" more fully.

Then I looked up K6OQK and saw 147.435 in Los Angeles. I think that one is world famous for sending the FCC packing,
and pushing the envelope well past the 7 dirty words. Maybe when Burt was involved it wasn't that way, but it became the
attractive nuisance of the amateur community.

...and what the hell does that have to do with the subject?

Southern California has a coordinating body that limits the bandwidth of 2 meter repeaters, because of a 15khz channel spacing.?
Burt mentions his involvement with the 147.435 repeater that does not follow the coordinating body's bandplan recomendation for
everyone else and uses a simplex frequency in it's pair so that people who jam with high power are still able to duplex.? Burt explains
on his website that the repeater actually pre-dated the coordinating body and was established as an AM and FM repeater in the 1960s
when 30khz channel spacing was in effect and when 2m FM was beginning to take over from 2m AM usage.? Many AM repeaters went
to FM on the transmitter and had AM and FM receiver inputs.? Most of the AM receivers were VFO control, so tuning in the FM
repeater transmitter was as simple as tuning to the side of the channel and allowing the skirt selectivity in the detector to "slope-detect"
converting the FM signal into a fairly good quality audio recovery.in an AM receiver.? For many years, at least since the 80's it was
(and maybe still is) the magnet for all the LIDs in So. Cal.? Burt says he has divorced himself from any hand in that machine after it went
south, so that is a relief to hear because I wouldn't want to promote repeater bad neighbors or wars.

Hi Bob,? I agree a flat repeater is nice to listen to. I have many articles about that subject on the web site.? Are you in a populated area where there is a lot of congestion on the air?
--
-
Regards, Karl Shoemaker
To contact me, please visit SRG's web site at?
for the current email address.

The easy standard I know:?? 2x(max audio freq + max dev) = bandwidth.? Although this isn't 100% accurate, it is the approximation the
FCC accepts for determining occupied bandwidth for narrow FM.? I beleive this method accounts for 90% of the energy, but there
is still occasional low level feculence outside this bandwidth approximation.? Maybe not a problem if stations are widely seperated
geographically, but should be looked out for.? There are more detailed formula, but not necessary.

So: 2x(3k+5k)=2x(8k)=16khz
and: 2x(6k+5k)=2x(11k)=22k??
and: 2x(5k+5k)=20khz
and: 2x(5k+4.2K)=18.4k
and: 2x(3k+4.2k)=14.4k?? I beleive this is what the 2meter coordinators specify in Southern California as they use 15khz spacing.
If only there was still room for 30khz channel spacing.

So the question, what is the max audio frequency and how much do you have to reduce the dev to accommodate the 15Khz
spacing and any drift?? Does anyone out there have a audio spectrum analyzer to find out the maximum frequency of the program
content after improvements are made with a good sounding mic and audio stages?? Human speech above 4k is uneccessary, but
harmonics from singing or screaming can go on up to 17K?.? Most of what you need for hard consonants is 1k to 3k.? Do you need
to sacrifice dev for hearing a baby scream?? Maybe you want to roll that off.? There is a lot of conflicting information out there from
people who equalize as they are often mixing many different musical sources and seeking a subjective "feel".?

Where the problem is: So. Cal specifies 4.2 max dev but radios shake out of the box with 4.5-6kc dev and almost no one will admit
that they ever check their radios, let alone performed Mic gain, Freq and Dev adjustments or even know what that is.? After bringing
a service monitor to club meetings for years, only 2 or 3 people were ever interested in keying their portable for a quick check.?

I noticed that OQKs website showed some compression and/or auto-leveling.? I don't much care for compression because it can only
make clipped stations sound worse, but maybe 3db of auto-levelling might help, as we see people who are modulating anywhere between
1kc and 6kc dev and varying mic levels, from timid to listening to the car stereo in the next lane on the freeway.? It is important to try to
"minimally" get people between 2 and 4kc dev at the repeater TX in order to avoid wearing out volume controls and still avoid pushing
the level into dev clipping that will increase intermodulation and harmonics that will require a post filter to avoid scratching the repeater users
15kc and 60miles away, because they can do the same to you just by tweeking their IDC pot.?

The other problem is having all this bandwidth available so that some users can abuse it and make a bad name for you.

If you want broadcast quality, maybe start by mortgaging the house to buy a broadcast station and frequency and actually have the room
to improve the audio quality of that broadcast station and maybe make some money from it as well.? I have heard some poor FM stereo
stations out there and a couple of really clean ones, so there is room out there for some purists with the desire.?

How / when does the fan normally operate in a DR-1X?

Thanks!
Jeff KC8VFN

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Try the input first. Not sure if you have to enable simulcast for this input to work.

One more point. You can use a transformer coupled input if you want to these pins because I assume that PL is the lowest frequency you will be passing?



73, Jim W7RY

Jim,

Can you give me some guidance in setting the QUANTAR to "Simulcast" so that I can use Pin 9 & 34 TX in?? I have a R2 VHF with the wireline card.? I had the software read my QUANTAR and then looked through the various pages in the software and find nothing that I recognize as "simulcast."

Burt, K6OQK

Have you tried old dos version


Have a blessed day/n4jem

Jim,

Can you give me some guidance in setting the QUANTAR to "Simulcast" so that I can use Pin 9 & 34 TX in?? I have a R2 VHF with the wireline card.? I had the software read my QUANTAR and then looked through the various pages in the software and find nothing that I recognize as "simulcast."

Burt, K6OQK

At 10/26/2022 06:54 AM, you wrote:

All my repeaters , regardless of using flat or non flat audio sound like simplex...

I think you're the first one here to state that... and it's true! Whether you pass unde-emphasized audio through the controller, or de-emph & pre-emph, you can get "flat audio" either way. In the latter case the key is to pick your 3 dB breakpoints such that both 6 dB/octave slopes are active across the entire audio band of interest. For pre-emphasis I use an R-C HPF with the 3 dB point set to ~9 kHz, & for de-emphasis an R-C LPF with a 3 dB rolloff around 60 Hz (I used to go down to ~30 Hz but recently discovered some dynamic range issues within the controller when applying that much de-emphasis, so moved it up a bit). The reason for going this route is to avoid having to individually pre-emphasize all the tone generators & speech synthesizers in the controller, which you must do if you're going to keep the RX audio unde-emphasized.

I'm a stickler when it comes to audio...too many years in broadcast engineering I guess lol...it's not hard to do either...but too many don't take the time to do it right..

I've never worked in broadcast, but still appreciate the sound of a well-engineered repeater that has flat audio response from <100 Hz to 5 or 6 kHz.

I've heard commercial repeaters sound like garbage...

One local linked repeater system switched from Mastr IIs to Quantars a few years ago. While I won't quite call the Quantars "garbage", it was certainly a large step backward in audio quality. One positive outcome of the switch was their 2 meter repeater, on a 15 kHz spaced channel with adjacent channels in close physical proximity, now plays nicely with those adjacents despite the short distance. The issue could have been resolved with the Mastr II given proper deviation adjustment & special audio processing, but with the Quantar's stock config the occupied BW is exceptionally narrow so I give that group kudos for making the change in that one case. But the other 440 repeaters are on 20 kHz spaced channels & don't need to be that narrow, especially when audio quality suffers.

and then there's the ham rptrs, using commercial equipment, set to narrow band yet the users are all wide band....ugh ..one KW TKR750 I know of is set to NB because the wideband filter died...easy to replace but the trustee was too lazy and put the rptr in NB mode....that's just stupid

On 2 meters around here sometimes operating the RX in narrow mode is necessary to avoid adjacent channel interference. Foortunately the G filters in the narrow strip aren't quite as narrow as some of the digital back-ended radios like the Motorola XPR when in 11k0 mode. With the latter you absolutely cannot get 5 kHz through that RX when set to 12.5 kHz - even in 25 kHz mode the IF is rather narrow & very unforgiving of off-channel signals. With the TKR I think you can still get close to 5 kHz deviation through without getting considerable distortion. But yeah if the wide IF chain died switching to narrow should be only used to keep the radio on the air until it can be repaired.

Bob NO6B

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Yes Burt. The input is fed from a balanced source.

An input value of -10dBm (@600 ohms, which is the SOURCE inpedence) will produce slightly less than maximum deviation.

This is the input used for simulcast systems which is multiple transmitters at different sites all on the same frequency. This method is used (broadband audio input) to keep all of the transmitters sending the same exact level and frequency response (along with the proper phasing) so good quality audio can be heard by the listening units.

Yes, you can use the Quantar as a separate receiver and transmitter at the same time. This is exactly how the Quanter is used in simulcast operation.

One more note... The simulcast transmit audio is processed with a UCSi or CSCi. Universal simulcast controller (or universal conventional simulcast controller) to maintain deviation limiting and either connect tone (in trunking) or PL or DPL in conventional modes which are both very low frequencies.

Voted audio is sent to the CSCi or the UCSi to be sent to the base stations.

Motorola used the term trunking base station, because they are not "repeaters" as hams would know them.

Nice on the Peeps!

73, Jim W7RY

Jim, W7RY,

Again, the QUANTAR stuff is new to me and I don't speak Motorolaese.? I presently have the QUANTAR set to to not be a repeater and to give me wide band audio out on pin 30 of the 50 pin TELC connector.? That seems to be working fine.? As you suggested, I should be able to input wide band audio through pins 9 & 34 via the 50 pin Teleco connector.? I am assuming those two pins are a balanced audio pair.? Trying those connections, I am unable to modulate the transmitter.? Have you ever used Pin 9 & 34 for audio input?

You suggest that I might need to set the radio to "Simulcast."? I understand the term "Simulcast," but not sure how it applies in this case.? I do have the software in my computer and I am able to talk to the radio.? Will doing that affect the ability to get the wide band audio out of the receiver at the same time?? Can you give me any guidance on setting the radio to "Simulcast?"

Again, my hope is to be able to use the QUANTAR's transmitter and receiver as independent units, just in the same rack frame.? I'm assuming that would be what's referred as using him with an external controller as far as set up goes.

By the way... many years ago I was given a new yellow hard hat to wear at construction sites.? A close buddy, W6ALX, saw me wearing it and stenciled on it in big letters, "Peeps."

Thanks,

Burt, K6OQK

Jim W7RY

Oct 23 ? #195037??

The general transmit audio input (+ and -) on the 50 pin telco connector.

You may need to set the station to simulcast to get this input active?

?

Jim, W7RY,

Again, the QUANTAR stuff is new to me and I don't speak Motorolaese.? I presently have the QUANTAR set to to not be a repeater and to give me wide band audio out on pin 30 of the 50 pin TELC connector.? That seems to be working fine.? As you suggested, I should be able to input wide band audio through pins 9 & 34 via the 50 pin Teleco connector.? I am assuming those two pins are a balanced audio pair.? Trying those connections, I am unable to modulate the transmitter.? Have you ever used Pin 9 & 34 for audio input?

You suggest that I might need to set the radio to "Simulcast."? I understand the term "Simulcast," but not sure how it applies in this case.? I do have the software in my computer and I am able to talk to the radio.? Will doing that affect the ability to get the wide band audio out of the receiver at the same time?? Can you give me any guidance on setting the radio to "Simulcast?"

Again, my hope is to be able to use the QUANTAR's transmitter and receiver as independent units, just in the same rack frame.? I'm assuming that would be what's referred as using him with an external controller as far as set up goes.

By the way... many years ago I was given a new yellow hard hat to wear at construction sites.? A close buddy, W6ALX, saw me wearing it and stenciled on it in big letters, "Peeps."

Thanks,

Burt, K6OQK

Jim W7RY

The general transmit audio input (+ and -) on the 50 pin telco connector.

You may need to set the station to simulcast to get this input active?

?

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Karl's (AK2O) has some great info on his SRG website too about flat audio and some great theory that I have observed with my own eyes.

Jim W7RY

Here is some additional good reading on the subject of FM Transmitter frequency response and some reasons it is limited in most FM transmitters - from Repeater-Builder no less:

I guess as long as you can extend the frequency response without violating Part 97.307, in particular Part 97.307(b), then I guess all is good.??

My concern would be that the splatter filter is there for a good reason - and it is what generally limits the response of the transmitter - so by forcing more bandwidth through the transmitter I would expect the chances of splatter to be higher.? The very low frequencies would be my main concern as they contain the most audio power and are most likely to be impacted by proximity effect.

I will leave it at that until I do some testing - and look at the spectral purity while doing so.

Daniel Woodie, CETsr

KC8ZUM

M: +1.513.478.9844

H: +1.513.231.1101

E: kc8zum@...

LinkedIn:

? ? ? ? ? ? ? ? ?

On Tue, Oct 25, 2022 at 11:07 PM Kevin Custer <kuggie@...> wrote:

On 10/25/2022 10:36 PM, Dan Woodie wrote:

-------------------BIG snip ----------------------------

I feel there are far more important things to be spending money and time on than trying to create a Hi-Fi repeater

------------------------BIG snip ---------------------

Daniel Woodie, CETsr

KC8ZUM

But that's one of the reasons this group exists - not most of the other things you wrote about.? Keep that in mind when replying to this group.? We're about highly technical stuff here.

And - just because some of the radios that users use are junk - doesn't mean we should be building repeaters that have substandard frequency response.?

I can also hear the difference between a properly built repeater and a stock "300Hz - 3kHz" one.? You want to hear a thing of beauty - listen to one of the WN3A built machines.? Observation of wider audio frequency response and properly built and set processing will change your opinion.

Kevin W3KKC

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THUMBS UP!

Jim W7RY

On 10/25/2022 10:36 PM, Dan Woodie wrote:

-------------------BIG snip ----------------------------

I feel there are far more important things to be spending money and time on than trying to create a Hi-Fi repeater

------------------------BIG snip ---------------------

Daniel Woodie, CETsr

KC8ZUM

But that's one of the reasons this group exists - not most of the other things you wrote about.? Keep that in mind when replying to this group.? We're about highly technical stuff here.

And - just because some of the radios that users use are junk - doesn't mean we should be building repeaters that have substandard frequency response.?

I can also hear the difference between a properly built repeater and a stock "300Hz - 3kHz" one.? You want to hear a thing of beauty - listen to one of the WN3A built machines.? Observation of wider audio frequency response and properly built and set processing will change your opinion.

Kevin W3KKC

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STOP hijacking threads please.

Jim W7RY

---------- Original Message ----------

From: John <jhaserick84@...>

To: [email protected], Burt K6OQK <biwa@...>

Date: 10/25/2022 8:38 PM

Subject: Re: [repeater-builder] QUANTAR VHF Audio Interface...

Yes, Burt, I also agree with that concept because it is better in those circumstances of low initial audio and to me it also makes sense to increase intelligibility when you are receiving noise on the repeater.? It does usually reduce the highs from them being selectively clipped, so the question is how do you boost the highs back when the clipping is done on pre-emphasized audio where flat audio is defined by the same voltage at the clipper when the input frequency is swept from lowest to highest frequency at the same input deviation? By adding high frequency boost after the clipper, and then more low pass filtering? Possibly easier and better to just eliminate the pre-emphasis components before the clipper, and add comparable pre-emphasis after the clipper so a little audio compression without reducing highs and still the same low pass roll-off. There must be a way to configure Kevin's clipper /filter to achieve this result.

To my thinking, the advantage from having no repeater compression or clipping is when you want to repeat a repeat times X in analog so as to not keeping adding background noise or distortion each time, at least on the link radios if a quiet link path. Guess that is one big advantage of digital repeaters?

John

On 10/25/2022 4:47 PM Burt K6OQK <biwa@...> wrote:

John,

I personally do not believe in the 5 kHz in and 5 kHz out thinking.? A part of the problem is that stations with low deviation will come through with low deviation and those with high deviation can hit the transmitter's limiter too hard.? Some believe that it's the responsibility of those stations to correct their deviation, and learn to use correct mic technique. My experience in that area has proven to be: Good Luck!

Please understand, I don't mean to be talking at you, but just intellectualizing with you...

To my way of thinking, a repeater is not a piece of test equipment to be used as a deviation tester.? It's a contraption to improve / enable communications.? Proper processing also protects the transmitter and adjacent channel spectrum in a less destructive way.? Anything I can do to make it simple, reliable, and pleasant, is a plus.? That's why I have always used appropriate audio processing on my repeaters.? I've gotten arguments from the unwashed telling me that it brings up the noise on the incoming signal. Well, yes, that's true, but you're going to have to turn up the volume at the user's end if you want to hear those stations anyway.? When you do that you are not only bringing up the noise heard by the repeater, but also any noise between and the repeater.? Having to turn the volume up and down while listening to a repeater gets tiring after a while.

For what it's worth,

Burt, K6OQK

Have a VXR-7000 running in repeater mode with the internal controller......it keys up and retransmits fine, when the hang time drops and the repeater unkeys, it resets/reboots itself, comes up flashing ** om the display, and then resets to its last configuration.....any ideas ? We thought maybe RF or SWR, but the SWR checks fine, and it does it on a dummy load as well.?

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The input is direct coupled. No transformers involved since the input passes down to 5 Hz.

73, Jim W7RY

Jim,

Thanks for your reply, and no, for some reason I did not see it earlier.? Are pins 9 & 34 a balanced pair?? How are they coupled in so as to have wide band audio? Electronically balanced, transformer, or each and unbalanced input?? I had seen those on another sheet and wasn't sure if they were data only and not capable of passing analog audio.

Thanks,

Burt, K6OQK

Jim W7RY

Oct 24 ? #195058??

Then you did not see my reply.

The general transmit input is uses for simulcast. It passes DC to 10 KHz with no issues.

Connector 17, (50 pin telco)Pins 9 and 34

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I know how to run the software in dealer mode, but once the software is running, I see no where to,change it…..the number in the software field is greyed out, cant type in there…..is it possible to do a hard reset on the repeater, restoring it to factory devaults?

Have a blessed day/n4jem