From robink4idc at gmail.com  Wed Apr  8 14:57:46 2020
From: robink4idc at gmail.com (K4IDC@comcast.net)
Date: Wed, 8 Apr 2020 13:57:46 -0500
Subject: [Rover] Fwd: WTB: Coaxial Transfer Relays or SPDT Relays
In-Reply-To: <CAJHj7F4xR+wQX=RU71S93HQBywchALENm9-MUfB21Tds0dJmpA@mail.gmail.com>
References: <CAJHj7F4xR+wQX=RU71S93HQBywchALENm9-MUfB21Tds0dJmpA@mail.gmail.com>
Message-ID: <CAJHj7F5T75P8UmHGQUgRcS+3uE8h4THZFpxjXLKtVv1SjnnYLQ@mail.gmail.com>

I'm looking for either three coaxial transfer relays or three pairs of SPDT
coaxial relays. These are for three VHF+ amplifier projects. Power handling
should be 500 watts or higher at VHF+ frequencies. Connectors and coil
voltages can be managed so those parameters aren't as important. Please
reply directly if you have any to offer for sale.

Thanks,
Robin Midgett K4IDC

From w2ev at yahoo.com  Wed Apr  8 16:26:48 2020
From: w2ev at yahoo.com (Ev Tupis)
Date: Wed, 8 Apr 2020 20:26:48 +0000 (UTC)
Subject: [Rover] Primary Batteries
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
Message-ID: <1476626051.1816401.1586377608154@mail.yahoo.com>

Hi List,

Could you offer me some insights?

I have a need to supply ~75 amps @ 12v during TX.? My plan was to put a battery (or two?) in my trunk along with the amplifier to keep leads short.

I'd keep that battery "topped off" by running some 6AWG from my under-the-hood battery.

Any recommendations for a battery for the trunk (or other insights)?

Ev, W2EV

From waisean at gmail.com  Wed Apr  8 17:23:35 2020
From: waisean at gmail.com (Sean Waite)
Date: Wed, 8 Apr 2020 17:23:35 -0400
Subject: [Rover] Primary Batteries
In-Reply-To: <1476626051.1816401.1586377608154@mail.yahoo.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
	<1476626051.1816401.1586377608154@mail.yahoo.com>
Message-ID: <CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>

The 100Ah AGMs I use top out at 30A or so continuous pull. We run a pair of
them with a worst case of about 45-50A worst case draw and usually much
less. With 75A expected draw you're looking at 3 of those in parallel or
more likely going for heavier batteries.

A lot of people like the 6V golf cart batteries in series+parallel to get
12V at the expected capacity and current rating. I'm using 12V batteries,
it's what I found.

I'm topping them off from the car while in motion. Definitely get some
heavy power poles, or rather the Anderson SB series connectors. You don't
want to overdraw your car battery while stopped. We disconnect when parked
and then reconnect in motion. I need to pick up a big marine battery switch
or something so I don't have the mechanical cycles on my connectors and
also to make it easier to switch (our first rove required a wrench to
disconnect 200Ah of battery from the car at each stop while on a rush. Not
my idea of fun)

I found really heavy gauge jumper cables, 4AWG or so, and have been using
that wire for connecting things. The jackets are probably overly thick but
it was the best price I found for that wire.

I fuse with 80A fuses. I probably could reduce that rating but I wanted to
leave headroom for the battery string to charge.

I've thought about all sorts of other enhancements but there are other
priorities and this works. Bring a fire extinguisher.

73/Yours in Scouting
Sean Waite, WA1TE

On Wed, Apr 8, 2020, 16:27 Ev Tupis via Rover <rover at mailman.qth.net> wrote:

> Hi List,
>
> Could you offer me some insights?
>
> I have a need to supply ~75 amps @ 12v during TX.  My plan was to put a
> battery (or two?) in my trunk along with the amplifier to keep leads short.
>
> I'd keep that battery "topped off" by running some 6AWG from my
> under-the-hood battery.
>
> Any recommendations for a battery for the trunk (or other insights)?
>
> Ev, W2EV
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

From rick1ds at hotmail.com  Wed Apr  8 17:31:39 2020
From: rick1ds at hotmail.com (Rick R)
Date: Wed, 8 Apr 2020 21:31:39 +0000
Subject: [Rover] Primary Batteries
In-Reply-To: <1476626051.1816401.1586377608154@mail.yahoo.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>,
	<1476626051.1816401.1586377608154@mail.yahoo.com>
Message-ID: <BN8PR03MB47400442F0C1377BC59CF31DFAC00@BN8PR03MB4740.namprd03.prod.outlook.com>

for one thing you can keep the engine on and the alternator keeping the voltage and current high. I always kept the van engine on while transmitting with my 350W 2m amp that takes about 50A. I used 2 marine batteries in series. Other options are golf cart batteries VERY HEAVY. Another alternative is a generator feeding an Astron 70A Power supply or putting 3 30Aswitching supplies in parallel.  
GL 73,Rick K1DS


From w2ev at yahoo.com  Wed Apr  8 19:12:29 2020
From: w2ev at yahoo.com (Ev Tupis)
Date: Wed, 8 Apr 2020 23:12:29 +0000 (UTC)
Subject: [Rover] Primary Batteries
In-Reply-To: <CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
	<1476626051.1816401.1586377608154@mail.yahoo.com>
	<CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>
Message-ID: <1743662684.1856985.1586387549430@mail.yahoo.com>

Thanks, Sean.? I'm hearing either golf cart batteries or marine batteries from others, too.

-Ev






On Wednesday, April 8, 2020, 5:23:48 PM EDT, Sean Waite <waisean at gmail.com> wrote: 





The 100Ah AGMs I use top out at 30A or so continuous pull. We run a pair of them with a worst case of about 45-50A worst case draw and usually much less. With 75A expected draw you're looking at 3 of those in parallel or more likely going for heavier batteries.?

A lot of people like the 6V golf cart batteries in series+parallel to get 12V at the expected capacity and current rating. I'm using 12V batteries, it's what I found.?

I'm topping them off from the car while in motion. Definitely get some heavy power poles, or rather the Anderson SB series connectors. You don't want to overdraw your car battery while stopped. We disconnect when parked and then reconnect in motion. I need to pick up a big marine battery switch or something so I don't have the mechanical cycles on my connectors and also to make it easier to switch (our first rove required a wrench to disconnect 200Ah of battery from the car at each stop while on a rush. Not my idea of fun)?

I found really heavy gauge jumper cables, 4AWG or so, and have been using that wire for connecting things. The jackets are probably overly thick but it was the best price I found for that wire.?

I fuse with 80A fuses. I probably could reduce that rating but I wanted to leave headroom for the battery string to charge.?

I've thought about all sorts of other enhancements but there are other priorities and this works. Bring a fire extinguisher.?

73/Yours in Scouting
Sean Waite, WA1TE 

On Wed, Apr 8, 2020, 16:27 Ev Tupis via Rover <rover at mailman.qth.net> wrote:
> Hi List,
> 
> Could you offer me some insights?
> 
> I have a need to supply ~75 amps @ 12v during TX.? My plan was to put a battery (or two?) in my trunk along with the amplifier to keep leads short.
> 
> I'd keep that battery "topped off" by running some 6AWG from my under-the-hood battery.
> 
> Any recommendations for a battery for the trunk (or other insights)?
> 
> Ev, W2EV
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

From w2ev at yahoo.com  Wed Apr  8 19:28:59 2020
From: w2ev at yahoo.com (Ev Tupis)
Date: Wed, 8 Apr 2020 23:28:59 +0000 (UTC)
Subject: [Rover] Primary Batteries
In-Reply-To: <1743662684.1856985.1586387549430@mail.yahoo.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
	<1476626051.1816401.1586377608154@mail.yahoo.com>
	<CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>
	<1743662684.1856985.1586387549430@mail.yahoo.com>
Message-ID: <6350949.1880921.1586388539098@mail.yahoo.com>

Adding to this thread...I see that there are three options to consider: Absorbent Glass Mat (AGM) Sealed Lead Acid (SLA) batteries, and lithium iron phosphate (LiFePO4).

Any comments on these in a high current environment?

Ev







On Wednesday, April 8, 2020, 7:12:44 PM EDT, Ev Tupis via Rover <rover at mailman.qth.net> wrote: 





Thanks, Sean.? I'm hearing either golf cart batteries or marine batteries from others, too.

-Ev






On Wednesday, April 8, 2020, 5:23:48 PM EDT, Sean Waite <waisean at gmail.com> wrote: 





The 100Ah AGMs I use top out at 30A or so continuous pull. We run a pair of them with a worst case of about 45-50A worst case draw and usually much less. With 75A expected draw you're looking at 3 of those in parallel or more likely going for heavier batteries.?

A lot of people like the 6V golf cart batteries in series+parallel to get 12V at the expected capacity and current rating. I'm using 12V batteries, it's what I found.?

I'm topping them off from the car while in motion. Definitely get some heavy power poles, or rather the Anderson SB series connectors. You don't want to overdraw your car battery while stopped. We disconnect when parked and then reconnect in motion. I need to pick up a big marine battery switch or something so I don't have the mechanical cycles on my connectors and also to make it easier to switch (our first rove required a wrench to disconnect 200Ah of battery from the car at each stop while on a rush. Not my idea of fun)?

I found really heavy gauge jumper cables, 4AWG or so, and have been using that wire for connecting things. The jackets are probably overly thick but it was the best price I found for that wire.?

I fuse with 80A fuses. I probably could reduce that rating but I wanted to leave headroom for the battery string to charge.?

I've thought about all sorts of other enhancements but there are other priorities and this works. Bring a fire extinguisher.?

73/Yours in Scouting
Sean Waite, WA1TE 

On Wed, Apr 8, 2020, 16:27 Ev Tupis via Rover <rover at mailman.qth.net> wrote:
> Hi List,
> 
> Could you offer me some insights?
> 
> I have a need to supply ~75 amps @ 12v during TX.? My plan was to put a battery (or two?) in my trunk along with the amplifier to keep leads short.
> 
> I'd keep that battery "topped off" by running some 6AWG from my under-the-hood battery.
> 
> Any recommendations for a battery for the trunk (or other insights)?
> 
> Ev, W2EV
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
Rover mailing list
Home: http://mailman.qth.net/mailman/listinfo/rover
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Rover at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

From w2ev at yahoo.com  Wed Apr  8 19:49:45 2020
From: w2ev at yahoo.com (Ev Tupis)
Date: Wed, 8 Apr 2020 23:49:45 +0000 (UTC)
Subject: [Rover] Primary Batteries
In-Reply-To: <6350949.1880921.1586388539098@mail.yahoo.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
	<1476626051.1816401.1586377608154@mail.yahoo.com>
	<CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>
	<1743662684.1856985.1586387549430@mail.yahoo.com>
	<6350949.1880921.1586388539098@mail.yahoo.com>
Message-ID: <1675745272.1887430.1586389785661@mail.yahoo.com>

Well...I found a very interesting document that will likely answer the question I asked.? In case anyone cares: http://www.sotabeams.co.uk/content/Batteries%20for%20portable%20use.pdf

Ev, W2EV







On Wednesday, April 8, 2020, 7:29:12 PM EDT, Ev Tupis via Rover <rover at mailman.qth.net> wrote: 





Adding to this thread...I see that there are three options to consider: Absorbent Glass Mat (AGM) Sealed Lead Acid (SLA) batteries, and lithium iron phosphate (LiFePO4).

Any comments on these in a high current environment?

Ev







On Wednesday, April 8, 2020, 7:12:44 PM EDT, Ev Tupis via Rover <rover at mailman.qth.net> wrote: 





Thanks, Sean.? I'm hearing either golf cart batteries or marine batteries from others, too.

-Ev






On Wednesday, April 8, 2020, 5:23:48 PM EDT, Sean Waite <waisean at gmail.com> wrote: 





The 100Ah AGMs I use top out at 30A or so continuous pull. We run a pair of them with a worst case of about 45-50A worst case draw and usually much less. With 75A expected draw you're looking at 3 of those in parallel or more likely going for heavier batteries.?

A lot of people like the 6V golf cart batteries in series+parallel to get 12V at the expected capacity and current rating. I'm using 12V batteries, it's what I found.?

I'm topping them off from the car while in motion. Definitely get some heavy power poles, or rather the Anderson SB series connectors. You don't want to overdraw your car battery while stopped. We disconnect when parked and then reconnect in motion. I need to pick up a big marine battery switch or something so I don't have the mechanical cycles on my connectors and also to make it easier to switch (our first rove required a wrench to disconnect 200Ah of battery from the car at each stop while on a rush. Not my idea of fun)?

I found really heavy gauge jumper cables, 4AWG or so, and have been using that wire for connecting things. The jackets are probably overly thick but it was the best price I found for that wire.?

I fuse with 80A fuses. I probably could reduce that rating but I wanted to leave headroom for the battery string to charge.?

I've thought about all sorts of other enhancements but there are other priorities and this works. Bring a fire extinguisher.?

73/Yours in Scouting
Sean Waite, WA1TE 

On Wed, Apr 8, 2020, 16:27 Ev Tupis via Rover <rover at mailman.qth.net> wrote:
> Hi List,
> 
> Could you offer me some insights?
> 
> I have a need to supply ~75 amps @ 12v during TX.? My plan was to put a battery (or two?) in my trunk along with the amplifier to keep leads short.
> 
> I'd keep that battery "topped off" by running some 6AWG from my under-the-hood battery.
> 
> Any recommendations for a battery for the trunk (or other insights)?
> 
> Ev, W2EV
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
Rover mailing list
Home: http://mailman.qth.net/mailman/listinfo/rover
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Rover at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

______________________________________________________________
Rover mailing list
Home: http://mailman.qth.net/mailman/listinfo/rover
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Rover at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

From va3cdd at rac.ca  Wed Apr  8 19:55:49 2020
From: va3cdd at rac.ca (Dean Denter)
Date: Wed, 8 Apr 2020 19:55:49 -0400
Subject: [Rover] Primary Batteries
In-Reply-To: <6350949.1880921.1586388539098@mail.yahoo.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
	<1476626051.1816401.1586377608154@mail.yahoo.com>
	<CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>
	<1743662684.1856985.1586387549430@mail.yahoo.com>
	<6350949.1880921.1586388539098@mail.yahoo.com>
Message-ID: <CA+90TQwR-bipGgvvgAYy2u_aNbHsGb7hHsQ=_tiWbEaaCj6pVw@mail.gmail.com>

LiFEPO4 is lightweight but lots of money, but you can use most of their
rated capacity (use a BMS to make sure you don't damage the battery -- a
lot of the commercial batteries have BMS circuits already built in, make
sure the BMS supports the configuration if you plan to use them in series
and/or parallel configurations) -- I use a 30AH battery for my 10GHz
hilltopping setup, it needs to be lightweight since it is part of a gear
pack that gets carried on my back occasionally.

SLA & AGM are both heavy weight but less expensive, be careful to not
discharge these below 11.5V or you will damage the cells and you will
likely only get 50-60% of the rated AH capacity without damaging the
batteries -- I usually use an automatic cutoff set to 11.8V to turn off the
power before the batteries get damaged.

For my rover I used standard wet-cell lead-acid marine batteries in my
rover -- make sure they have ventilation & are properly restrained to not
tip.  If you go with 12V wet-cell marine batteries, be careful to look for
DC-type and not DP or Starting batteries (DC = Deep Cycle).  As mentioned
above, I have an old commercial cut off circuit that shuts down the power
if the voltage drops too low.  I was running about 400AH of series/parallel
Group24 DC-type marine batteries to power the rover with a 20A charging
circuit that is relay switched from an ignition-only circuit so it only
charges when the engine is running.  The rover has an FT847 (~2A RX / 20A
TX), an IC746 (~2A RX / ~25A TX), a dual band FM mobile (1A RX / 10A TX), &
3 transverters (.5A RX / 10A TX) with a couple of HTs and other gear -- I
still paper log, but would like to add in a laptop at some point.  I
usually have enough power to make it thru a VHF contest weekend -- but
recent contests have only been local 6-8 hour sprints due to work
commitments.

regards,
Dean -- VA3CDD


On Wed, Apr 8, 2020 at 7:29 PM Ev Tupis via Rover <rover at mailman.qth.net>
wrote:

> Adding to this thread...I see that there are three options to consider:
> Absorbent Glass Mat (AGM) Sealed Lead Acid (SLA) batteries, and lithium
> iron phosphate (LiFePO4).
>
> Any comments on these in a high current environment?
>
> Ev
>
>
>
>
>
>
>
> On Wednesday, April 8, 2020, 7:12:44 PM EDT, Ev Tupis via Rover <
> rover at mailman.qth.net> wrote:
>
>
>
>
>
> Thanks, Sean.  I'm hearing either golf cart batteries or marine batteries
> from others, too.
>
> -Ev
>
>
>
>
>
>
> On Wednesday, April 8, 2020, 5:23:48 PM EDT, Sean Waite <waisean at gmail.com>
> wrote:
>
>
>
>
>
> The 100Ah AGMs I use top out at 30A or so continuous pull. We run a pair
> of them with a worst case of about 45-50A worst case draw and usually much
> less. With 75A expected draw you're looking at 3 of those in parallel or
> more likely going for heavier batteries.
>
> A lot of people like the 6V golf cart batteries in series+parallel to get
> 12V at the expected capacity and current rating. I'm using 12V batteries,
> it's what I found.
>
> I'm topping them off from the car while in motion. Definitely get some
> heavy power poles, or rather the Anderson SB series connectors. You don't
> want to overdraw your car battery while stopped. We disconnect when parked
> and then reconnect in motion. I need to pick up a big marine battery switch
> or something so I don't have the mechanical cycles on my connectors and
> also to make it easier to switch (our first rove required a wrench to
> disconnect 200Ah of battery from the car at each stop while on a rush. Not
> my idea of fun)
>
> I found really heavy gauge jumper cables, 4AWG or so, and have been using
> that wire for connecting things. The jackets are probably overly thick but
> it was the best price I found for that wire.
>
> I fuse with 80A fuses. I probably could reduce that rating but I wanted to
> leave headroom for the battery string to charge.
>
> I've thought about all sorts of other enhancements but there are other
> priorities and this works. Bring a fire extinguisher.
>
> 73/Yours in Scouting
> Sean Waite, WA1TE
>
> On Wed, Apr 8, 2020, 16:27 Ev Tupis via Rover <rover at mailman.qth.net>
> wrote:
> > Hi List,
> >
> > Could you offer me some insights?
> >
> > I have a need to supply ~75 amps @ 12v during TX.  My plan was to put a
> battery (or two?) in my trunk along with the amplifier to keep leads short.
> >
> > I'd keep that battery "topped off" by running some 6AWG from my
> under-the-hood battery.
> >
> > Any recommendations for a battery for the trunk (or other insights)?
> >
> > Ev, W2EV
> > ______________________________________________________________
> > Rover mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/rover
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Rover at mailman.qth.net
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
>
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

From w2ev at yahoo.com  Wed Apr  8 20:22:49 2020
From: w2ev at yahoo.com (Ev Tupis)
Date: Thu, 9 Apr 2020 00:22:49 +0000 (UTC)
Subject: [Rover] Primary Batteries
In-Reply-To: <CA+90TQwR-bipGgvvgAYy2u_aNbHsGb7hHsQ=_tiWbEaaCj6pVw@mail.gmail.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
	<1476626051.1816401.1586377608154@mail.yahoo.com>
	<CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>
	<1743662684.1856985.1586387549430@mail.yahoo.com>
	<6350949.1880921.1586388539098@mail.yahoo.com>
	<CA+90TQwR-bipGgvvgAYy2u_aNbHsGb7hHsQ=_tiWbEaaCj6pVw@mail.gmail.com>
Message-ID: <1795285510.1950166.1586391769392@mail.yahoo.com>

Hi Dean,
That last paragraph is gold.? It gives me real insight into how you are configured and why.? 

I need to think about how to transpose that into how I hope to operate.

Thanks, Dean!
Ev






On Wednesday, April 8, 2020, 7:56:01 PM EDT, Dean Denter <va3cdd at rac.ca> wrote: 





LiFEPO4 is lightweight but lots of money, but you can use most of their rated capacity (use a BMS to make sure you don't damage the battery -- a lot of the commercial batteries have BMS circuits already built in, make sure the BMS supports the configuration if you plan to use them in series and/or parallel configurations) -- I use a 30AH battery for my 10GHz hilltopping setup, it needs to be lightweight since it is part of a gear pack that gets carried on my back occasionally.

SLA & AGM are both heavy weight but less expensive, be careful to not discharge these below 11.5V or you will damage the cells and you will likely only get 50-60% of the rated AH capacity without damaging the batteries -- I usually use an automatic cutoff set to 11.8V to turn off the power before the batteries get damaged.

For my rover I used standard wet-cell lead-acid marine batteries in my rover -- make sure they have ventilation & are properly restrained to not tip.? If you go with 12V wet-cell marine batteries, be careful to look for DC-type and not DP or Starting batteries (DC = Deep Cycle).? As mentioned above, I have an old commercial cut off circuit that shuts down the power if the voltage drops too low.? I was running about 400AH of series/parallel Group24 DC-type marine batteries to power the rover with a 20A charging circuit that is relay switched from an ignition-only circuit so it only charges when the engine is running.? The rover has an FT847 (~2A RX / 20A TX), an IC746 (~2A RX / ~25A TX), a dual band FM mobile (1A RX / 10A TX), & 3 transverters (.5A RX / 10A TX) with a couple of HTs and other gear -- I still paper log, but would like to add in a laptop at some point.? I usually have enough power to make it thru a VHF contest weekend -- but recent contests have only been local 6-8 hour sprints due to work commitments.

regards,
Dean -- VA3CDD


On Wed, Apr 8, 2020 at 7:29 PM Ev Tupis via Rover <rover at mailman.qth.net> wrote:
> Adding to this thread...I see that there are three options to consider: Absorbent Glass Mat (AGM) Sealed Lead Acid (SLA) batteries, and lithium iron phosphate (LiFePO4).
> 
> Any comments on these in a high current environment?
> 
> Ev
> 
> 
> 
> 
> 
> 
> 
> On Wednesday, April 8, 2020, 7:12:44 PM EDT, Ev Tupis via Rover <rover at mailman.qth.net> wrote: 
> 
> 
> 
> 
> 
> Thanks, Sean.? I'm hearing either golf cart batteries or marine batteries from others, too.
> 
> -Ev
> 
> 
> 
> 
> 
> 
> On Wednesday, April 8, 2020, 5:23:48 PM EDT, Sean Waite <waisean at gmail.com> wrote: 
> 
> 
> 
> 
> 
> The 100Ah AGMs I use top out at 30A or so continuous pull. We run a pair of them with a worst case of about 45-50A worst case draw and usually much less. With 75A expected draw you're looking at 3 of those in parallel or more likely going for heavier batteries.?
> 
> A lot of people like the 6V golf cart batteries in series+parallel to get 12V at the expected capacity and current rating. I'm using 12V batteries, it's what I found.?
> 
> I'm topping them off from the car while in motion. Definitely get some heavy power poles, or rather the Anderson SB series connectors. You don't want to overdraw your car battery while stopped. We disconnect when parked and then reconnect in motion. I need to pick up a big marine battery switch or something so I don't have the mechanical cycles on my connectors and also to make it easier to switch (our first rove required a wrench to disconnect 200Ah of battery from the car at each stop while on a rush. Not my idea of fun)?
> 
> I found really heavy gauge jumper cables, 4AWG or so, and have been using that wire for connecting things. The jackets are probably overly thick but it was the best price I found for that wire.?
> 
> I fuse with 80A fuses. I probably could reduce that rating but I wanted to leave headroom for the battery string to charge.?
> 
> I've thought about all sorts of other enhancements but there are other priorities and this works. Bring a fire extinguisher.?
> 
> 73/Yours in Scouting
> Sean Waite, WA1TE 
> 
> On Wed, Apr 8, 2020, 16:27 Ev Tupis via Rover <rover at mailman.qth.net> wrote:
>> Hi List,
>> 
>> Could you offer me some insights?
>> 
>> I have a need to supply ~75 amps @ 12v during TX.? My plan was to put a battery (or two?) in my trunk along with the amplifier to keep leads short.
>> 
>> I'd keep that battery "topped off" by running some 6AWG from my under-the-hood battery.
>> 
>> Any recommendations for a battery for the trunk (or other insights)?
>> 
>> Ev, W2EV
>> ______________________________________________________________
>> Rover mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/rover
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:Rover at mailman.qth.net
>> 
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
> 
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
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From va3cdd at rac.ca  Wed Apr  8 20:55:33 2020
From: va3cdd at rac.ca (Dean Denter)
Date: Wed, 8 Apr 2020 20:55:33 -0400
Subject: [Rover] Primary Batteries
In-Reply-To: <1795285510.1950166.1586391769392@mail.yahoo.com>
References: <1476626051.1816401.1586377608154.ref@mail.yahoo.com>
	<1476626051.1816401.1586377608154@mail.yahoo.com>
	<CAGz_XJxM1JXw-UJvkJzFj40apGG9L=Kz4VziRUjbJE=XsNG7tg@mail.gmail.com>
	<1743662684.1856985.1586387549430@mail.yahoo.com>
	<6350949.1880921.1586388539098@mail.yahoo.com>
	<CA+90TQwR-bipGgvvgAYy2u_aNbHsGb7hHsQ=_tiWbEaaCj6pVw@mail.gmail.com>
	<1795285510.1950166.1586391769392@mail.yahoo.com>
Message-ID: <CA+90TQxaQsVYNmDySs3HvgZh9k5XHxQ+pLeV7enRmC3UXTW9qQ@mail.gmail.com>

1 more important piece of info I forgot:  planned discharge rates.

SLA/AGM & other Lead-Acid:  I was told a long time ago, plan for C/10
maximum discharge rate & don't go above C/8.

LiFePO4:  I have seen discharge rates of C or higher commonly used, we use
a 20AH LiFePO4 battery for the 10GHz liaison station that is ~2A RX / ~20A
TX for around 8hours with 5-10% TX duty cycle without issues.

What this means is the ~400AH marine flooded-cell lead-acid battery bank I
use in my rover is really only capable of 400/10=40A maximum planned
discharge rate -- this combined with the weight of the lead-acid battery
bank may eliminate it from your planned 75A discharge rate since 10x 75AH
batteries is a lot of weight (normal Group24 marine batteries are around
75AH).  My battery bank is 6x Group24s, but they are refurbished so I
tested their capacity (refurb == drained, cleaned, replaced acid, retested,
etc by someone who has done the refurbishment for off-grid solar systems
before).

Hope this info helps.

regards,
Dean -- VA3CDD


On Wed, Apr 8, 2020 at 8:26 PM Ev Tupis via Rover <rover at mailman.qth.net>
wrote:

> Hi Dean,
> That last paragraph is gold.  It gives me real insight into how you are
> configured and why.
>
> I need to think about how to transpose that into how I hope to operate.
>
> Thanks, Dean!
> Ev
>
>
>
>
>
>
> On Wednesday, April 8, 2020, 7:56:01 PM EDT, Dean Denter <va3cdd at rac.ca>
> wrote:
>
>
>
>
>
> LiFEPO4 is lightweight but lots of money, but you can use most of their
> rated capacity (use a BMS to make sure you don't damage the battery -- a
> lot of the commercial batteries have BMS circuits already built in, make
> sure the BMS supports the configuration if you plan to use them in series
> and/or parallel configurations) -- I use a 30AH battery for my 10GHz
> hilltopping setup, it needs to be lightweight since it is part of a gear
> pack that gets carried on my back occasionally.
>
> SLA & AGM are both heavy weight but less expensive, be careful to not
> discharge these below 11.5V or you will damage the cells and you will
> likely only get 50-60% of the rated AH capacity without damaging the
> batteries -- I usually use an automatic cutoff set to 11.8V to turn off the
> power before the batteries get damaged.
>
> For my rover I used standard wet-cell lead-acid marine batteries in my
> rover -- make sure they have ventilation & are properly restrained to not
> tip.  If you go with 12V wet-cell marine batteries, be careful to look for
> DC-type and not DP or Starting batteries (DC = Deep Cycle).  As mentioned
> above, I have an old commercial cut off circuit that shuts down the power
> if the voltage drops too low.  I was running about 400AH of series/parallel
> Group24 DC-type marine batteries to power the rover with a 20A charging
> circuit that is relay switched from an ignition-only circuit so it only
> charges when the engine is running.  The rover has an FT847 (~2A RX / 20A
> TX), an IC746 (~2A RX / ~25A TX), a dual band FM mobile (1A RX / 10A TX), &
> 3 transverters (.5A RX / 10A TX) with a couple of HTs and other gear -- I
> still paper log, but would like to add in a laptop at some point.  I
> usually have enough power to make it thru a VHF contest weekend -- but
> recent contests have only been local 6-8 hour sprints due to work
> commitments.
>
> regards,
> Dean -- VA3CDD
>
>
> On Wed, Apr 8, 2020 at 7:29 PM Ev Tupis via Rover <rover at mailman.qth.net>
> wrote:
> > Adding to this thread...I see that there are three options to consider:
> Absorbent Glass Mat (AGM) Sealed Lead Acid (SLA) batteries, and lithium
> iron phosphate (LiFePO4).
> >
> > Any comments on these in a high current environment?
> >
> > Ev
> >
> >
> >
> >
> >
> >
> >
> > On Wednesday, April 8, 2020, 7:12:44 PM EDT, Ev Tupis via Rover <
> rover at mailman.qth.net> wrote:
> >
> >
> >
> >
> >
> > Thanks, Sean.  I'm hearing either golf cart batteries or marine
> batteries from others, too.
> >
> > -Ev
> >
> >
> >
> >
> >
> >
> > On Wednesday, April 8, 2020, 5:23:48 PM EDT, Sean Waite <
> waisean at gmail.com> wrote:
> >
> >
> >
> >
> >
> > The 100Ah AGMs I use top out at 30A or so continuous pull. We run a pair
> of them with a worst case of about 45-50A worst case draw and usually much
> less. With 75A expected draw you're looking at 3 of those in parallel or
> more likely going for heavier batteries.
> >
> > A lot of people like the 6V golf cart batteries in series+parallel to
> get 12V at the expected capacity and current rating. I'm using 12V
> batteries, it's what I found.
> >
> > I'm topping them off from the car while in motion. Definitely get some
> heavy power poles, or rather the Anderson SB series connectors. You don't
> want to overdraw your car battery while stopped. We disconnect when parked
> and then reconnect in motion. I need to pick up a big marine battery switch
> or something so I don't have the mechanical cycles on my connectors and
> also to make it easier to switch (our first rove required a wrench to
> disconnect 200Ah of battery from the car at each stop while on a rush. Not
> my idea of fun)
> >
> > I found really heavy gauge jumper cables, 4AWG or so, and have been
> using that wire for connecting things. The jackets are probably overly
> thick but it was the best price I found for that wire.
> >
> > I fuse with 80A fuses. I probably could reduce that rating but I wanted
> to leave headroom for the battery string to charge.
> >
> > I've thought about all sorts of other enhancements but there are other
> priorities and this works. Bring a fire extinguisher.
> >
> > 73/Yours in Scouting
> > Sean Waite, WA1TE
> >
> > On Wed, Apr 8, 2020, 16:27 Ev Tupis via Rover <rover at mailman.qth.net>
> wrote:
> >> Hi List,
> >>
> >> Could you offer me some insights?
> >>
> >> I have a need to supply ~75 amps @ 12v during TX.  My plan was to put a
> battery (or two?) in my trunk along with the amplifier to keep leads short.
> >>
> >> I'd keep that battery "topped off" by running some 6AWG from my
> under-the-hood battery.
> >>
> >> Any recommendations for a battery for the trunk (or other insights)?
> >>
> >> Ev, W2EV
> >> ______________________________________________________________
> >> Rover mailing list
> >> Home: http://mailman.qth.net/mailman/listinfo/rover
> >> Help: http://mailman.qth.net/mmfaq.htm
> >> Post: mailto:Rover at mailman.qth.net
> >>
> >> This list hosted by: http://www.qsl.net
> >> Please help support this email list: http://www.qsl.net/donate.html
> >
> > ______________________________________________________________
> > Rover mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/rover
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Rover at mailman.qth.net
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> > ______________________________________________________________
> > Rover mailing list
> > Home: http://mailman.qth.net/mailman/listinfo/rover
> > Help: http://mailman.qth.net/mmfaq.htm
> > Post: mailto:Rover at mailman.qth.net
> >
> > This list hosted by: http://www.qsl.net
> > Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> Rover mailing list
> Home: http://mailman.qth.net/mailman/listinfo/rover
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Rover at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html