A place to discuss internet linking of radio equipment, such as eQSO, FRN, iRLP, Echolink, and other such systems.
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Posts: 189
Joined: 23 Nov 2017, 20:14
Call Sign: 26DG04
Location: Democratic Peoples Republic of Devon

Re: CB RoIP?

Post by 26mb04 »

Keep up the good work, I haven't used my DIY zello gateway recently because I've had other priorities. I'm still very much interested in seeing how this plays out.
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Posts: 81
Joined: 19 Jan 2012, 14:13

Re: CB RoIP?

Post by rpcomms »

Hello 26MB04
yes,I instead too having now literally spent hundreds and hundreds of hours R&D on this project,not just the interface but ,contacting mfrs,emails,pushing for CTCSS,researching ctcss modules,4g routers,voice scrambling options,ariel types,ground isolations,installation optimising performance tests,local RFI\EMI reducing of base installations,PSU types (removing smp issue snow resolved & know why ),mesh linking via zello,backup system if internet goes down Parrot modes,Parrot software/hardware research and contacting software engineers,UPS AC UPS DC systems,racking and enclosures,icom IDAS,Icom 4G PTT LTE,PMR446idas connectivity and code plugs,CB hardware connectivity,in car mobile gateways with x-band linking,mobile car pc,running desktop pc of dc-dc ATX power boards god the list just goes on and on
Plus pcb design cad,parts,BOMs,etc
Ive tried to iron out every possible Bug and failure point,interfacing,and redundancy systems as I want the system very robust,not slap dash chucked together.

Zello backbone "mesh-linking"bases-done tested,yes can link bases to bases to bases to form a meshed system
Zello devices tested via wifi and wired ethernet,plus tested abroad linked back to uk,for lag checking issues with hardware
some issues were found,like jamming ptt if base radio turned off! (resolved)
Lack of backup power supply systems,was another key issue for pc,radio,interface unit-def a must have
Back up alternative internet and failure points-so that was another key issue,with internet service providers,I found 4G routers were the most reliable in end ditching any cabled internet service provider,just too many links in chain for failure points,which it did!
Ariel testing of bases for saturated coverage area in a typical urban environment and height factor (ground affect on Line of Sight comms use)-for 27mhz 65ft mast from ground worked best
1/4 ground plane 3 leg radials (light weight,lesswind loading at height,less metal in air)
1/2wave vertical (inc J Pole-Ground Plane version we developed\fixed the design faults)@65ft
terrain hilly surrounding area

At height say located on a high spot,a lower angle radiation pattern was required like a proper ground plane 5/8 for Line of sight system use(NOT DXING!!! ),as we want to optimise for Line of sight ONLY .

Fully Isolated Ground isolator RF transformers killed off Earth to dc ground issues with SMP power supplies and the mast earthing of ariel,I had to countless hours research and design,source correct ferrite's, test & build these from scratch ,that fixed a host of noise issues
All new cb\ham\commercial kit (99%) are dc grounded chassis,the older cb kit is fully isolated chassis.
SMP PSU do not like the DC ground coming into contact with real EARTH or Frame Earth ground of PSU,thats why they go nasty!!!
DC rail noise
all sorts of yucky stuff,if you use a metal pole into EARTH,your Ariel bracket connected is Earthed,your coax is Earthed (braid),so to is your new shiny cb dc grounded now to Earth!
SMP PSU do not like this!easy to test with scope and spectrum analyser\loop ariel
They are other issues with smp psu but not going into it this deep here including the pcb grounding system on the interface.

UHF to CB?VHF cross banding via zello-worked-No issues there apart from interfacing equipment

dpmr to cb-yes tried it,yes it works via zello (or any other mode Am ssb dmr)

we also developed a ID system on zello to ease device types of users,that really helps as can see what the users logined in on device+ID number.

Voice scramblers and voice security-tested completed

Cooling fans,Rack enclosures,radio cooling -additional fan blowers

OK,Zello/Parrot mode backup-Ive researched this and it is possible to do now,via hardware interface\pc computer
originally it would not work due to the software needed upgrading,this has now been completed
And just recently hardware chip version based Basic parrot mode,im looking at now
How do we get semi duplex on a simplex frequency you may ask????
Use split ctcss mode(now on Randy 3HT and hopefully newer cb radios coming out soon!)
also works on advanced PMR446 HTs and commercial versions!
WE could not test cb ctcss split-mode( but could on uhf ) ,but did test cb CTCSS single tone mode(all cb do this with ctcss fitted)
at the time,but after so nagging feature been added now and hopefully other new models

why split ctcss?
well one its legal and is best compromise,rather than repeater shift most cb wont support it and legalities

so example

27mhz base gateway\parrot mode split ctcss channel (no mobile to mobile in gateway mode)
TX 27,105Mhz CTCSS tone 67Hz
RX 27.105Mhz CTCSS tone 118.8Hz

MObiles/Portable HTs
TX 27,105Mhz CTCSS tone 118.8Hz
RX 27.105Mhz CTCSS tone 67.Hz

So no zello traffic,parrot mode ON
car to car
ht to ht
ht to car
all voice traffic goes over zello channel so the can listen
Now if Zello user keys up,Parrot mode killed,Normal voice traffic via Zello transmits to all radios!
Once Zello user finished,users can talk back ,then after a pre determined time zello user finishes,Parrot mode kicks back in.
If Internet lost,Parrot mode stay ON,local comms only

the Aux channel for Simplex\Simplex CTCSS gateway is ch16-16(tone) EU
channels 21-21,22-22,23-23 EU for gateway\Parrots split ctcss operation

so where are we now?
UHF tested
CB tested,Ham version WIP
Parrot mode (software version tested)-hardware version on going parts issues covid
Ariel\Coax\Masts\Ground Isolators-Completed

PCB Interfaces
Rev 1-tested USB version
Rev 2.00 semi tested-On Hold Parts issues,Icom Idas repeater modules interface-RS232
Rev 3.00 stopped upgraded to rev 4.00 RS232
Rev 4.00 basic\advanced versions on going RS232
Rev 5.0 TBC
Rev 6.00 Vehicle\Base\Icom 4glte ptt\zello ports-On going design with daily updates,remote control head,dual hardware parrot,voice scrambling,X band linking on-board radios,blue tooth could be a future option-RS232

we wont be supporting VOX COS its too unreliable for HTs at the moment
plus duty cycles too on TX heavy.

reviewing\how to interface 27/29mhz
CRT Mega Pro-base\mobile use-need a sample unit
TTi 5289-base\mobile use-need a sample unit
GPE Randy 3-HT\Car use (wont do ham 10m bands @29mhz)-soon to be ordered in
GPE new mobile releases with CTCSS split mode(we waiting)
Lincoln 2+(special modified and enhanced fm performance version prob on cards,as Ive done CRT SS6900 V3.1 full upgrades and it shares lot of the electronics,main pcb )

66-88 Lowband
Retvis & Stabo 66-88mhz lowband mobile for commercial\amateur use\cb 69mhz export

UHF-Retivis RT9000D
Icom iDas system dpmr
CRT PMR446,Retvis PMR446,plus other compatible sets

4G LTE PTT-Icom Ic-501M & option interface cable-Just recently added.

I will add a note-this is not going to be cheap to end user,as there's a lot of hardware involved, I would say probably a group venture thing,or radio club to start off initially.
and then see how it takes off first,baby steps first.

The problem I found if you skimp in some areas
you compromise the design
the redundancy of the system.

given the fact you want this on 27/7,365 days a year ON to ensure a decent service,hardware choice play an important part of it,if reliability is required.

Its still in "on going"test phase at the moment,as we wait for new sets to add to our "feasible bases"use.
The other key Issue dont deploy at your home "QTH site" unless 100% sure you wish to lose some RF bands or put up with de-sensing other radio kit!
this is often overlooked by end users,who may turn them on and off giving random service!
Not ideal,especially if linking bases into a Network system .
some systems maybe "closed private" others maybe "open general use"but monitored
Also remote shut down and control options,Ident ID also im looking at currently.

It takes a lot of your time to build and research,test but havnt given up as getting very close to getting the full Monty versions tested,this covid stuff has not helped electronics industry in parts,so why ive had to revamp design of interface card.

we plan to finalise two fully operation "meshed bases" to show case system and options available.
Ham (pending requirements)bands
Commercial LMR\Export

thats the goal,and see how that goes.

Personally I think personal radio needs updating in some technical areas to keep up to date with current tech,like ROIP etc

As for CB,PMR-446 personal radio ,I feel rather than create another new system ,expand on whats already there for instance

digital voice am\fm\SDR ssb\dpmr cb 6.25khz @30watts ERP
expanded channels within the band 25.000 to 27.595MHz or 26.500-27.595mhz {not using any critical licensed users freqs]+ UK FM band with allocated channel area for ssb only dx\local hobby users away from am\fm users
Clear away of easier new protocol interfacing on cb\pmr446 for connectivity to internet & IT devices
Increase PMR-446 to 32 channels ,with mobiles\bases at 2w erp 17-32 gateway,roip,repeaters usages (registered Ident)

Dual band PMR-446\27mhz combo units-Once approval of new mobiles and bases,that would be handy.

My one wish would be 69MHz Personal Radio band as used now in some EU states @25-50Watts erp
Its got a bit more grunt range wise,shorter ariels,and noise floor a little lower than 25-30mhz band.

All the above is really addition tools,NOT a replacement as DXers,general chat is part of this band,inc business users.

Some users want a more PMR style comms good for voice links\groups\emergency nets-usage or a way to extend range or access radio via a IT device ie tablet,phone,PC or areas where bases cannot get further out because of local terrain,linking means addition bases can for a meshed linked system in remote areas or where even now some cell phone coverage can be "iffy"still!
South cornwall,farwest,mid wales are some examples

CTCSS on CB 27mhz will also now help further with less interference heard ,it wont rid it but least keep your sanity levels from noise sources mobile,base,portable,protect gateway\repeaters used from DX\skip etc on 27mhz band

why im suggesting to get ball rolling ch16-16 EU 2.00khz max dev & UK band FM-Narrow 2.00/[2.50khz old MPT-1320]max dev,as a new ctcss net channel.

dont forget EU band is now 2.00khz max deviation (including ctcss tone 300Hz dev 60% dev=1.25khz spacing 10khz)on all current ETSI Multi_norm sets
inc UK band*

*Old MPT-1320 2.5khz dev peak\max inc CTCSS 350Hz dev 60% dev=1.5khz spacing 11.25khz
* all multi-Norms work on new ETSI standards on EU\UK FM side so will be max 2.00khz EU or UK bands ,why now incompatible issues arise with older cb kit sounds quieter.(note this can be fixed on older kit,ive done it)
higher fm deviations can distort audio on the newer Multi-Norms if deviation is too excessive due to tighter filters {455HT} and fm discriminator audio set up at 1.25khz deviation=60% {more sensitive}

deviation base on 1khz test tone injected
15khz LP filter on modulation meter-max dev

oh the new tactical blade TNC Ariel and drop in charger for Randy 3 will be out shortly !

dont forget CH16-16(single tone)EU\UK try and use as new CTCSS net channels\monitoring CB
maybe emg 1\2 channel can be programmed into these new sets with ctcss?

keep you posted more to come


Rob P
Posts: 81
Joined: 19 Jan 2012, 14:13

Re: CB RoIP?

Post by rpcomms »

OK little update
well we have the President Randy 3 now available,apparently working very well
CTCSS equipped so ready for gateways and Simple parrot repeaters uses

Also new CTCSS user network call\chat channel
on CH16-16 EU\UK im trying to encourage new users to CTCSS use on 27mhz where less qrm noise free comms can exsist on NFM mode.

A KIND NOTE:Ham radio\EXport USA radios modified stuff please check your equipment NFM is setup correctly for these systems,5khz deviation exceeds the filters in these new ETSI Multi-Norm radios and older MPT-1320 radios,causing audio TX distortion,low audio on rx on YOUR KIT due to switched to the wrong fm bandwidth system.
Ham HF kit can be corrected with correct service monitor and a good radio tech,please dont spoil it for other legal users.
Also be aware some USA imported Export radios are often not set up correctly for UK\EU NFM system for use on CB Mulit-Norm sets,totally different specifications to Amateur USA FCC VS ETSI Euro CB radios.
Any doubt get you kit checked\modified or msg me here for help,id prefer at very least to hear nice clear super narrow fm rather than choppy over deviated wide fm and low rx audio reports on legal users equipment when there nothing technically wrong with the legal kit,its purely FM specifications are different users need to made aware off.

Mulit -Norm to Multi Norm should NOT present any issues at all unless mfr has messed up something!

EU-Max dev 2.00khz ctcss 300Hz dev 60% mod=1.25khz dev
UK-Max dev 2.20khz ctcss 350Hz dev 60% mod=1.5khz dev

deviation on Tx audio based on 1khz @50mV rms input to micro fully limited
with 15khz LPF
RX audio based on 3-6dB change from 60% dev to 100% dev for max audio output across a 4ohm resistive load on speaker o\p socket.(there are mods to correct this-ask)

Progress -well COVID has seriously hit electronics field,parts etc has caused me to re-design the Radio Interface Card part that links to the pc and cb radio.

Plus addition operation requirements wanted from the interface inc hardware parrot,2 radio ports ,X band linking ,dtmf controllers,vehicle interface card version and 4G LTE link-in ,so thers been delays delays delays,plus IM waiting on some new CB radios (mobiles)to be released with CTCSS \CTCSS Split Tone modes on them for the base station tests.

I have ordered up a small base station antenna to trail out min size base antenna VS max size base antenna to see what can be achieved with smallest base antenna systems but optimised best for Line of Sight,as in most cases NOT all cb users can put up 18-21ft monsters and in most cases these are best suited for long range DXing rather than Line Of Sight comms.
Last time the 1/4wave ground plane works best \compromise antenna at about the 50 feet,but opted for a reduced size base loaded antenna with ground planes,mainly due to a lot less weight at a higher height 65FT+ to over come less gain\efficiency of size\wind loading\less mass of metal on mast,so be conducting tests soon.
Ordering\trails of double shielded 10mm coax and new ground isolator rf transformers to test,help reduce induce noise,static and adding dc grounding to reduce static and ground isolation.

working on the dual mode Zello gateway\parrot module this time using a hardware chip based than pc software based
Split CTCSS tone for semi-duplex tone shift on parrot\gateway modes was tested last week,that went very well on UHF version,so split freq use is not needed now on parrot repeater.
Instead using split CTCSS,New cb will also when have them here do same testing have to wait till new cb sets arrive now.
So in mean time im working on another redesigned base interface card pcb and parrot module+dtmf decoding.

Im no PIC programmer either so need to learn code too or find a good software engineer for this project!

feels a bit 1 step forward 10 steps back the last few months ,but ill keep on going as really want to see this through till the end.

Rob P 73's
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