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[KI6GEA]

Bear with me, I'm new.. got my General a few weeks ago and am just learning about this stuff.

I have an IC-705 installed in my truck ('21 Tahoe) and am currently powering it off an AC adapter in the center console (PAE Kx33) and it is working fine. However I do notice when I stop at stop lights and the auto shutdown of the engine happens, the radio will sometimes switch over to internal battery power. So the AC adapter doesn't deliver constant power apparently.

I'm adding a Xiegu 125b amplifier this coming week, and am trying to figure out the best way to power the amp and the radio, hopefully without having to go through the dash to the car battery. I would also like to maintain the "portable" aspect of the rig for times I may want to take it out for a hike.

My thought was a Bioenno battery under the seat, that is being charged by that AC adapter. I see Bioenno has so 40a and 50a models, which should be enough to power both the amp and the radio. I would like to make it as "clean" as possible, so maybe a small Rigrunner from the battery to give me a small panel under the seat to connect the amp and radio? Again I would like to be able to remove the radio occasionally to capitalize on it's portable ability.

Also thinking I would use the Bioenno AC charger provided with the battery, also under the seat, to keep the battery charged.

Is this a good solution, and if not, what would you suggest?

Also, some might suggest just getting a 100w mobile radio. I'm set on the 705. It is a near perfect fit in the center console, and I also use it extensively for VHF/UHF on the road. See pic:

https://photos.app.goo.gl/RBsaUZGEkxQH5RLp9

73,
KI6GEA

[WA2EIO]

Some things to consider:

From what I understand the Bioenno type battery should not be left on a charger indefinitely, so you would have to remember to disconnect it sometime after the battery is fully charged.   Also, if you need to keep the engine running for the charger to work, how will you do a full charge of the battery; it should not be done 'piecemeal' but in one continuous charge.   Completely charging a 50Ah battery will take about 5 hours with the Bioenno charger. 
For portable operation, you can use the Bioenno, but why not run a cable to the vehicle's battery?   It is still relatively easy to disconnect it and remove the unit(s) for portable operation.  Also, the more PowerPole connections you have the more likely you will have voltage drops.   While not much of a problem with powering the rig by itself at 10 Watts output, it may be a problem for the  (approx.) 20 amps needed by the amplifier.
Realize that a 50Ah battery would use a 10 Amp charger, so be sure your car's connection can handle the power needed for the charger.  (10 A at 14 volts =140 Watts; so be sure that your car's connection can supply at least 150 Watts.  More if you intend to charge while still operating the rig from that same connection.)

[KI6GEA]

Thank you very much for the feedback. My reluctance to use the car battery is mainly because I'm don't understand their power output, and not wanting to dig into the dash/firewall if I don't have to.. But I do have a friend that has a car audio shop/business, so I'm sure he could help me with this. Would a power run from the car battery to something like a RigRunner under the seat to connect the amp and radio to be a better solution?

I'm very grateful for the guidance, 73.

Some things to consider:

From what I understand the Bioenno type battery should not be left on a charger indefinitely, so you would have to remember to disconnect it sometime after the battery is fully charged.   Also, if you need to keep the engine running for the charger to work, how will you do a full charge of the battery; it should not be done 'piecemeal' but in one continuous charge.   Completely charging a 50Ah battery will take about 5 hours with the Bioenno charger. 
For portable operation, you can use the Bioenno, but why not run a cable to the vehicle's battery?   It is still relatively easy to disconnect it and remove the unit(s) for portable operation.  Also, the more PowerPole connections you have the more likely you will have voltage drops.   While not much of a problem with powering the rig by itself at 10 Watts output, it may be a problem for the  (approx.) 20 amps needed by the amplifier.
Realize that a 50Ah battery would use a 10 Amp charger, so be sure your car's connection can handle the power needed for the charger.  (10 A at 14 volts =140 Watts; so be sure that your car's connection can supply at least 150 Watts.  More if you intend to charge while still operating the rig from that same connection.)

[W9IQ]

Modern vehicles contain a state of charge / coulomb counter device that manages the charging of the battery. These have been put in place to eek out a bit more MPG for the vehicle rating. While the old school advice was to connect directly to both terminals of the battery, this is no longer advised as that may inadvertently bypass the battery charge monitoring system resulting in a dead vehicle battery.

The modern best practice is to only wire to the positive of the battery and find a ground connection on the vehicle frame or engine. Make certain to properly fuse the added positive line at the battery. As an alternative, many modern vehicles have a very robust power distribution bus into the vehicle interior to support the ever growing array of consumer electrical accessories. You may very well find a suitable unused branch circuit that you can use with the simple addition of a fuse into the fuse/distribution block. This will save the hassle of having to pass wire through the firewall.

- Glenn W9IQ

[KI6GEA]

Thank you Glenn, I really appreciate the advice. Will this fused power line from the battery, or possibly this branch circuit, provide enough juice for both the amp and the radio?

Modern vehicles contain a state of charge / coulomb counter device that manages the charging of the battery. These have been put in place to eek out a bit more MPG for the vehicle rating. While the old school advice was to connect directly to both terminals of the battery, this is no longer advised as that may inadvertently bypass the battery charge monitoring system resulting in a dead vehicle battery.

The modern best practice is to only wire to the positive of the battery and find a ground connection on the vehicle frame or engine. Make certain to properly fuse the added positive line at the battery. As an alternative, many modern vehicles have a very robust power distribution bus into the vehicle interior to support the ever growing array of consumer electrical accessories. You may very well find a suitable unused branch circuit that you can use with the simple addition of a fuse into the fuse/distribution block. This will save the hassle of having to pass wire through the firewall.

- Glenn W9IQ

[K4PIH]

I had a loaner vehicle when mine was in the shop that had the shut down option. I was able to go through the dash menu and override that but when I did a manual stop to go into a store and shut the vehicle off I had to reprogram when restarting. Personally I hate the engine shut off feature but that's me.

On most of those systems you can program the vehicle to remain idling when stopped. I'd think that was the easiest route to go, but you may have to reprogram after a complete shutdown.

[K1KIM]

I had a loaner vehicle when mine was in the shop that had the shut down option. I was able to go through the dash menu and override that but when I did a manual stop to go into a store and shut the vehicle off I had to reprogram when restarting. Personally I hate the engine shut off feature but that's me.

On most of those systems you can program the vehicle to remain idling when stopped. I'd think that was the easiest route to go, but you may have to reprogram after a complete shutdown.

A auto repair shop might have the ability to reprogram the ECU to permanently disable the auto shut-off feature.

I had that on a car once. Hated it. But it was amazing how fast it started back up and went when depressing the throttle.

[KI6GEA]

I just read the manual (gasp!) of my new Tahoe, and learned there is a button right on the dash to disable the auto shutdown. It resets each time the car is shut off, but at least I can disable it for times I'm using the amp. I'm only going to use the amp for the HF antenna I think. I have an antenna duplexer for the vhf/UHF amp...

So I have this little Powerwerx 30amp power supply, I could put that under the seat where I was going to put the battery, and run that off the AC plug in the center console. And run both the amp and the radio off the Powerwerx I think?

I had a loaner vehicle when mine was in the shop that had the shut down option. I was able to go through the dash menu and override that but when I did a manual stop to go into a store and shut the vehicle off I had to reprogram when restarting. Personally I hate the engine shut off feature but that's me.

On most of those systems you can program the vehicle to remain idling when stopped. I'd think that was the easiest route to go, but you may have to reprogram after a complete shutdown.

[K1KIM]

So I have this little Powerwerx 30amp power supply, I could put that under the seat where I was going to put the battery, and run that off the AC plug in the center console. And run both the amp and the radio off the Powerwerx I think?

I thought the PS needed 120VAC in to get the 13.8vDC /30A out.

Please clarify what you are trying to do. I am confused.

[WA2EIO]

Your safest (and simplest!) would be to follow w9IQ's post.   Have your friend with the audio shop run an AWG-8 or 10 gauge cable direct from the battery to the passenger compartment.   )If he does this type of thing often, he is probably familiar with the correct connection protocols.)  The cable will have a fuse at the battery end. (usually around 30 Amps)  Securely mount the rig and amp in the car, and run a heavy cable from the 'ground' stud on them to a secure chassis ground.   Many use one of the seat bolts, which should be securely fastened to the frame of the car.
You already have a (relatively) unlimited supply of 12 VDC from your battery to power the rig and amp, so using an AC power supply would needlessly complicate things and is not necessary.

[K0UA]

I just read the manual (gasp!) of my new Tahoe, and learned there is a button right on the dash to disable the auto shutdown. It resets each time the car is shut off, but at least I can disable it for times I'm using the amp. I'm only going to use the amp for the HF antenna I think. I have an antenna duplexer for the vhf/UHF amp...

So I have this little Powerwerx 30amp power supply, I could put that under the seat where I was going to put the battery, and run that off the AC plug in the center console. And run both the amp and the radio off the Powerwerx I think?

I had a loaner vehicle when mine was in the shop that had the shut down option. I was able to go through the dash menu and override that but when I did a manual stop to go into a store and shut the vehicle off I had to reprogram when restarting. Personally I hate the engine shut off feature but that's me.

On most of those systems you can program the vehicle to remain idling when stopped. I'd think that was the easiest route to go, but you may have to reprogram after a complete shutdown.

Your new, so we are going to go easy on you.  

BUT you are really really really messing up thinking about putting AC/DC power supplies in your vehicle to run 100 watt amplifiers. And I mean in a big way. Forget ALL of this nonsense, and do the thing you DO NOT want to do. And that is run a power cable under the hood to the battery/ground as Glen outlined and start hooking up these DC appliances (rig and amp) up to DC. You re not going to be able to pull the amount of current you need to run a 100 watt amp with AC to DC conversion from some wimpy little AC inverter in your vehicle. You can get away with it with your 10 watt transceiver, although on general principals even that is a power wasting double conversion solution, not even to mention the noise spikes inverters might put on your power line. In other words, this just isn't done. Not a good idea. The proper solution to almost ANY problem is to always bite the bullet and do that thing you do not want to do.

Now lets hear more about this QRP to 100 watt amplifier you intend to run with your 705. Make, model, and specifications.  Please don't be turned off by my "frank" analysis, I am trying to set you on the proper path.  You are now in the ditch, but we all are here to help pull you out.

[AC7CW]

At one point in time, older car without a computer, I shopped at a surplusser that had lead acid batteries. I put a resistor in series to limit the worst case current into the battery. I left it connected to the cigar lighter all the time, didn't care about battery life much because replacement cost was low but the battery was fine. I ran it like that for a year or two with no problems and the battery lasted. Lead acid batteries can be charged piecemeal and can be floated all the time.

[W9IQ]

The combination of the IC-705 and the 100 watt amp will draw a peak current of around 25 amps on voice SSB and CW.

If you run 15 feet of 10 gauge wire to the battery positive terminal, the peak voltage drop on that piece of wire will be around 0.4 volts. The fuse and the ground connection will probably add another 0.2 volts or so of peak drop. So at peak current draw, plan about a 0.6 volt drop. Most radios and amplifiers will handle this as the running voltage will be 13.8 volts putting you at 13.2 volts on peak current draw. So as James stated, get rid of the power supply and stop plugging the 705 into the inverter. Connect everything to the new wire to the battery. Put a 40 amp fuse at the battery on this positive wire.

I operated 100 watts from my Yukon for many years. I didn't want to run a new wire so I took a slightly different approach. I put everything in the back of the vehicle (remote head to the front) and plugged everything into the 10 amp accessory socket in the back. But I added a standard AGM battery directly across the 12 volt outlet. This battery would handle the peak current draw of the radio (voice SSB) and would automatically be charged while the vehicle is running and the radio didn't demand the peak amps. The 12 volt outlet shut off when the ignition was turned off so I didn't need to worry about one battery draining the other when parked. There was no need for any additional circuit as the voltage drop in the Yukon wiring harness automatically gave priority to the added battery when the current demand was high. Don't attempt to operate the radio for an extended period when the vehicle is turned off or the start-up charging current may open the 10 amp fuse.

A more modern approach to my Yukon method is to substitute super capacitors for the added battery. This takes a little more surrounding circuitry to properly manage the charging of the super capacitor bank but it does a great job of shaving off the peak current demand.

- Glenn W9IQ

[KI6GEA]

Thanks James, I appreciate your frankness and guidance. I put this out there for this very reason. I'm here to learn. Hopefully one day I'll be able to share my experience with others, once I get some..

It finally sunk in that I need to get power from the car battery. I'm going to do that.

The Amp is a Xiegu 125B. Specs:

Frequency Range: 0.5-54 MHz
Maximum Output Power: 1.8-30 MHz >110 Watts / 50 MHz >90W
Maximum Ambient Operation Temp: 131 Fahrenheit(55 Celsius)
Gain: 13 dB (+/-2dB)
Spurious Suppression: >50 dB
Supply Voltage: 12-15 Volts DC
Transmit Current Draw: @ max output 30 Amps
Receive Current Draw: @ max 700 mA
ATU Frequency Range: 1.8-30 MHz & 50-54 MHz
ATU Tuning Range: 14-500 Ohms

So the only question I have remaining is this. Say my car audio buddy gets power from under the hood to under the seat. I'll also make sure he addresses the fusing and grounding needs... So could I put this power into a RigRunner to distribute to both the amp and the radio?

If this would be an issue I could just continue powering the radio the way it is now, off the AC outlet in the console. Running it off the battery would be nice though as this would run around the auto shutoff issue.

Thanks again, I really appreciate your help with this.

Chris
KI6GEA

I just read the manual (gasp!) of my new Tahoe, and learned there is a button right on the dash to disable the auto shutdown. It resets each time the car is shut off, but at least I can disable it for times I'm using the amp. I'm only going to use the amp for the HF antenna I think. I have an antenna duplexer for the vhf/UHF amp...

So I have this little Powerwerx 30amp power supply, I could put that under the seat where I was going to put the battery, and run that off the AC plug in the center console. And run both the amp and the radio off the Powerwerx I think?

I had a loaner vehicle when mine was in the shop that had the shut down option. I was able to go through the dash menu and override that but when I did a manual stop to go into a store and shut the vehicle off I had to reprogram when restarting. Personally I hate the engine shut off feature but that's me.

On most of those systems you can program the vehicle to remain idling when stopped. I'd think that was the easiest route to go, but you may have to reprogram after a complete shutdown.

Your new, so we are going to go easy on you.  

BUT you are really really really messing up thinking about putting AC/DC power supplies in your vehicle to run 100 watt amplifiers. And I mean in a big way. Forget ALL of this nonsense, and do the thing you DO NOT want to do. And that is run a power cable under the hood to the battery/ground as Glen outlined and start hooking up these DC appliances (rig and amp) up to DC. You re not going to be able to pull the amount of current you need to run a 100 watt amp with AC to DC conversion from some wimpy little AC inverter in your vehicle. You can get away with it with your 10 watt transceiver, although on general principals even that is a power wasting double conversion solution, not even to mention the noise spikes inverters might put on your power line. In other words, this just isn't done. Not a good idea. The proper solution to almost ANY problem is to always bite the bullet and do that thing you do not want to do.

Now lets hear more about this QRP to 100 watt amplifier you intend to run with your 705. Make, model, and specifications.  Please don't be turned off by my "frank" analysis, I am trying to set you on the proper path.  You are now in the ditch, but we all are here to help pull you out.

[K0UA]

Yes, the small powerpole distribution block would work well. I am doing just that for my HF and VHF/UHF rig and antenna controller in my truck. something like this would work for you.

https://www.amazon.com/Position-Distribution-Powerpole-Connectors-PD-4/dp/B071LHY6MV