The KID as 70MHz RF remote repeater

[A J Coop]

Hello Forum users;
Just a few days ago my brother set up and used a 70MHz band remote repeater station for a major sporting event held in our state.
I set up the KID in his Ford ranger "with canopy" 300AH battery, WhizBang Jr & BTS installed 250W PV, all the necessary breakers!
During his post the repeater stopped working, the event managers are now blaming the KID for the damage?
I fumed at the thought of the KID I installed doing such a thing!

I am asking the forum for opinions please, so I can shove it in the event managers face...

During this time there was a Fridge Freezer, chews about 8A of juice, when starting, turning on.
Having a heated talk with my brother I am certain that the KID has been used in this sort of application in Americas climate...
The KID is UL listed... AND I INSTALLED IT!

The Radios involved are two 70MHz mobile radios linked together, Radio 1 RX (receives), Radio 2 TX (Transmits) uncertain witch radio snufft it or both! may be RX (Brother Thinks)

Nothing else was powered by the kid, Battery was 100% in float

I think that's it...

Opinions!!

A J COOP

[boB]

What was the battery voltage you were seeing when it was in operation ?

What are the radios rated for for voltage range ?

Charge controllers can also emit RFI and sometimes they can be at some inconvenient frequencies... 
70.0 - 70.5 MHz is evidently not a US ham band and I am assuming that is what you are using ?
I don't suppose that the KID controller is just emitting some EMI at your frequency of operation ?

What do the radios (TX/RX) do now ?  Do they light up ?  Did they smoke ?

etc...

boB

[A J Coop]

Thank you boB;
I am in Australia.
I am not with my brother on the event trial... he told me as much as possible.
Uncertain of the battery voltage at the time, (KID & Batt 12V)  a stab in the dark between 13.5 (Float) and below 15V (Bulk, taking in the temp compensation). He said the KID was in float so <13.5V there about with the loads, he was in the bush so shading on the PV would of put the KID in FloatMPPT (NO Relay ticks, I asked), he didn't say anything about rebulking.

The radio system is 12V, desighned for car use 10V (Low batt voltage) to <15.5V (Car altinator voltage).

These radios are not HAM radios (from memory Phillips branded). 70MHz is our VHF Gov mobile Radio network and some others, soon to be killed off...

RFI, EFI, EMI, Yes that thoght did cross my mind, did kind of shut me up.. the radios was about 1/2 metre (1 1/2 - 2 feet) away from the controller, I do have RF scanners and they do play up when my controller is in use, all over the spectrum, The kid has good shielding and the Radios them self have good shielding... Possible?

The radios light up, NO MAJIC SMOKE, just dont work, from what my brother tells me.

Light bolb, Many yeas ago I helped my brother at one stage we had a radio that was iccorectly programed, had the wrong freqs in it. I hope thats the issue, they just havent realised it yet! I'll ask.

Thanks boB

A J Coop

[ClassicCrazy]

I would check all the power connections to the radio's . Loose connections might be the problem or even poor connection at fuse - if it isn't what you mentioned that the radio's just went off frequency or something. No way to diagnose the problem unless someone is there with digital volt meter seeing what is happening at the radio end of power wiring to make sure there isn't a large voltage drop.  And also at the other end to make sure the battery voltage is okay too.

Larry

[A J Coop]

G'Day Larry;
    Thank you, the event is over for my brother now, there is no way for those pointers to be eyeballed.
When a large voltage drop occurs the radios will just reboot and go about doing what they do, eg starting car engine.
The power connecter on the other hand, ah, the old cigarette lighter socket or accessory socket, at the KID end I installed heavy duty (15A rated), that same socket powered the fridge freezer, weeks before the event, it was fine, ended up hard wiring it to the busbar and whizbang.
The radio end NO IDEA, guessing 20+ years old and not well maintained.

I used to be in the event, found it not to be of international event standard, I quit after 4 years of not getting better...
Had words with my brother before reading your response Larry and he got wind that few more radios played up during the event, the caretaker of the event equipment, had stowed the equipment under a tarp in his back yard, "radios included"? he wasn't certain. (may never know)
I got real angary that the radios may have been stored under a tarp for a year, the event is yearly, no wonder the radios played up.
Many years ago I seen and worked these radios, they are tough robust, but not to be stored under a TARP in the weather, I SAY NO MORE.

Looks to me the standards of the event is getting worse glad I left, my brother is now the same way. He said no more, He loved doing the event.

Thank you Larry

A J coop

[ke6cvh]

Possibly a more in depth description of how/why you concluded the radio is fried?  Did you since connect it to a nice and clean linear power supply to see if it works?  Since the charge controller was connected to what I think you described as a lead acid was it a wet cell?  Did you disable the different charge cycles?  I had a KID go into maintenance charge which normally I do not do.  It blew a fan I had running off the aux output and I confirmed since the aux output is not regulated so it increased along with the charge cycle blowing the fan.  Allot of radios can take around 15 volts but you need to check with the literature and see what the range of input voltages are and verify if it accidentally went into a maintenance cycle exceeding those specifications.  Just some ideas to put out there?  I am not normally on the forum but on it now because I am not satisfied with the lack of literature in the manual regarding the lithium ion function.  Am I supposed to just select it and see what happens after that?  I'm a big tech manual oriented person so felt wanting allot more.  Hopefully the forum will get the answers I seek and all of them.  Best regards

[A J Coop]

Hello Ke6cvh:
                Thank you for your response, and sorry about my late response!!
It was not me or my brother that said the radios went belly up! It was the event managers that blamed the KID for the malfunction. The managers of the event have not done any testing of the radios concerned? Made me suspicious that is was the poor state of the radios... or programming.
At the time of the malfunction my brother said the radios are quiet and he transmitted the RX (receive) radio seed to repeat TX (transmit) on the other , that may confuse you, two radios piggy backed is the best way of explaining that.
The battery is a SLA, 300Ah 12V, none of the charge cycles disabled, my brother has limited experience with solar, but has a wealth of radio experience!
The radios are hand me downs, from the state fire service, they are very good radios, correction they where very good radios...
The radios where not connected to a AUX or LOAD outputs, I connected a heavy duty accessory socket or the old cigarette lighter socket straight to a POS busbar, which has the KID POS, Batt POS and a fridge/freezer, the NEG to the WhizBang Jr.
These radios are designed for emergency service use (Fire) having the static from pumps, the resting and starting of the trucks would be above or there about the same voltages as the kid and the same if not worse dirty power supply going in to the radios, from my experience being a volunteer for our State Emergency Service these radios are hooked straight to the batteries, from memory the only thing I noticed was a water proof blade fuse just after the battery.
Lithium interesting I just started playing with 18650 and LiPol, whole different kettle of fish! Lots of data sheet reading and more reading, head ache...
One thing I did notice about Li ION is very narrow voltage, charge and depleted, having issues with float? Lithium being volatile I think I will play with them and get to know them before switching from SLA...
I will attach a CGR18650 (Panasonic) Individual Li ION data sheet.. may be of use?
Good luck.

[RossW]

One thing I did notice about Li ION is very narrow voltage, charge and depleted, having issues with float? Lithium being volatile I think I will play with them and get to know them before switching from SLA...

If you can accept the slight reduction in energy density, you might consider LiFePO4 technology instead.

I switched to "Lithium" from lead-acid almost 5 years ago and love it to bits. The very "narrow" voltage range is nowhere near the inconvenience it initially seems to be (in terms of estimating remaining capacity), but then again - voltage alone has never been a good way to guess SoC in an active system. I have almost 50 kWh of lithium storage for my home/office/workshop and wouldn't ever consider going back to lead-acid in any of its forms.

[A J Coop]

Hello RossW
       I have looked at the LiFePO4!! (lately I been searching for LiFeSO4 DUMB) Seen a few posts on it, done some digging to see who sells it in Australia and hum, seen it once in my regular shop and now it's gone!!
These 18650 and Li-Pol are just to play with before switching, I only have 26 of these 18650's and 2 Li-Pol, and there all old laptop and tablet batteries... I will need to have more than a few 18650's to have 5KWh, it's far from what I have now.
The LiFePO4 is the ticket no argument from me, AUSTRALIA NEEDS TO DO SOME CATCHING UP, there are stores that sell them but I see Chinese writing all over it!! I am turning away from Chinese made, due to bad experiences... 
I have a little saved up, by the time my SLA's die I should have enough $$ and see LiFePO4 in regular supply at my regular store..
LiFePO4 have about 10 - 15 years of life in them ? I have been a bit uncertain about SOC, now days I have a narrow sun to PV ratio (Worse in the winter) due to development, also the (very) south east Australian weather, can be a little hard to estimate usage and recharge.
The most amount of time not fully charging the SLA's have been 3 days, I've been careful not to exceed that!
Do LiFePO4 like going without full charging cycles? and a bunch of other questions, I may post a LiFePO4 chat... Do some more digging before that....

Thank you

[RossW]

Do LiFePO4 like going without full charging cycles?

My experience is that LiFePO4 (hereafter LFP) behave much more like capacitors than conventional batteries.
They don't mind not being in float for days or weeks at a time. They take what they can, and then give most of it back, without complaint or bribes.

I chose to import *ALL* of mine because I couldn't find a single, solitary "honest" importer. I don't begrudge someone making a fair margin, but when I can import them, pay all the freight, customs, duty, port charges, GST, handling etc on a small quantity, and STILL be 50% the price of any of the domestic suppliers, I know they're ripping me off.

It is NOT HARD to import them yourself. You can clear them yourself, or employ the services of a clearing agent. I've done both. One costs time, the other costs money. Just do it mate.

[mike90045]

Just remember, not to fully charge the FLP (or any Li based battery) nor to deeply discharge it either.   In the middle, it's all wonderful.

[A J Coop]

Thanks fellas; (mike90045 & RossW)
Sorry for how late, Work has been a killer sooo many full days of work *#!?, Can't even write this reply without someone ringing me up....
AH the pressure to get LFP , good pointers thanks again.

Good news...   Got word back from my brother about the 70MHz repeater, it was the repeater "Tail" (TX)
If any one don't know what the tail is..
It's where the TX (transmitting) radio keeps transmitting for a pre-determined time after the RX (Receiving) input has stopped being received, I hope I've made sense... The Tail of a transmission.

When my brother told me that I so wanted to slap those managers faces, with their radios 
SO it was not the KID, all this time! "No sorry",  my bum, nothing, WELL 
"Programming" where these people get their diplomas from "I don't KNOW"  .

Thank you all who commented offering advice and pointers, MUCH  appreciated.

Thank you again all.
Until next time KEEP 

[ClassicCrazy]

Thanks fellas; (mike90045 & RossW)
Sorry for how late, Work has been a killer sooo many full days of work *#!?, Can't even write this reply without someone ringing me up....
AH the pressure to get LFP , good pointers thanks again.

Good news...   Got word back from my brother about the 70MHz repeater, it was the repeater "Tail" (TX)
If any one don't know what the tail is..
It's where the TX (transmitting) radio keeps transmitting for a pre-determined time after the RX (Receiving) input has stopped being received, I hope I've made sense... The Tail of a transmission.

When my brother told me that I so wanted to slap those managers faces, with their radios 
SO it was not the KID, all this time! "No sorry",  my bum, nothing, WELL 
"Programming" where these people get their diplomas from "I don't KNOW"  .

Thank you all who commented offering advice and pointers, MUCH  appreciated.

Thank you again all.
Until next time KEEP 

Often called the hang time or carrier delay .
Here is explanation from repeater builder webpage
"Carrier delay - When you're monitoring a repeater and the person talking into the repeater un-keys his transmitter, you hear the squelch tail from the repeater's receiver. Then, the repeater's transmitter remains keyed anywhere between 1/2 second and 5 seconds, in other words its transmitter "hangs" on during the "carrier delay" before it "drops out". Some repeaters insert a beep or other type of tone or multiple tones during the hang time. This tone or tones can be a "courtesy beep" or it can be telemetry signaling that certain links or other devices are connected. The purpose of the carrier delay timer on a repeater is to eliminate the repeater's transmitter from chattering on and off when the repeater's receiver is receiving a noisy, choppy signal. In the early days when all the repeaters were based on vacuum tubes and used mechanical relays this timer saved much wear and tear on those relays. Todays solid state repeaters do not have this issue, but a chattering transmitter combined with an already choppy fluttering signal into a repeater is even more difficult to hear. Another purpose for the carrier delay is for testing. You can "kerchunk" (key your radio into a repeater momentarily) and monitor its signal level coming back to you."
http://www.repeater-builder.com/tech-info/repeater-term.html

Larry

[boB]

When I hear "tail", I usually think squelch tail which is right after the hang time.

boB

[A J Coop]

I was trying keeping it simple!

When I worked these radios there was no courtesy beep, no "from memory" CTCSS or DCS just a delay of 2 seconds.
Those in the know pick up on it, those who don't just need a simple translation, thank you for the detaild translation .

"The person talking into the repeater un-keys his transmitter, you hear the squelch tail from the repeater's receiver"
The way my brother explaind it, the TX radio was the Tail not the RX radio. The RX is just RX you hear nothing from the RX it's TX, what they are meant to say "the Receivers squelch tail to the repeater's transmitter" is what you hear?

"Then, the repeater's transmitter remains keyed anywhere between 1/2 second and 5 seconds"
Sounds more like this system and faild due to the way it was proramed, they may have put a CTCSS when their should not have been, simple mistake. I don't know.
The transmitter did not respond to receiver because receiver had no CTCSS? The repeater reciver & transmitter also field radios need that CTCSS for it to work.

Well its's nice to hear that the KID did not disrupt the comms of the event, some sort of apology from the blamers would have been nice, such is life...