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trigo(at)mail.telepac.pt
Guest

Posted: Sat Jul 27, 2013 2:53 am Post subject: 14V or 28V

Guys



I suppose this has been discussed before, but my laziness to search in the

archives makes me raise this issue again.

In the RV-10 that I am building, I am thinking in using a 12V(14V)

electrical system, most probably based in the Nuckolls's Z-14 architecture,

with the VP-X Pro box.



However, when searching for the Comm radios to choose from, I found that the

best radios, in terms of transmitting power (16W), are 28V.

Should I consider changing all the electric system to 28V, or is it possible

to have a 14V system and include a 14/28 voltage "converter" to feed the

radio?



All opinions welcome

Regards

Carlos

mrspudandcompany(at)veriz
Guest

Posted: Sat Jul 27, 2013 5:55 am Post subject: 14V or 28V

 	  Quote: 	
		   In the RV-10 that I am building, I am thinking in using a 12V(14V)

 electrical system, most probably based in the Nuckolls's Z-14 

 architecture,

 with the VP-X Pro box.



 However, when searching for the Comm radios to choose from, I found that 

 the

 best radios, in terms of transmitting power (16W), are 28V.

 Should I consider changing all the electric system to 28V, or is it 

 possible

 to have a 14V system and include a 14/28 voltage "converter" to feed the

 radio?


	




        28 volt systems have become the normal for many new production

        aircraft.  You can use lighter fat wires and thus save a bit of 

weight.

        All of the electrical components are available in either voltage.

        I would recommend that you go with one voltage or the other, and not 

try to

        run a dual voltage machine.  Just keep in mind that if you go with a 

28 volt

        system, you must keep all other electrical items such as, starter, 

lighting,

        contactors and anything else plugged into the system, compatable 

with the

        28 volts.



        Roger

ceengland7(at)gmail.com
Guest

Posted: Sat Jul 27, 2013 5:56 am Post subject: 14V or 28V

On 07/27/2013 05:49 AM, Carlos Trigo wrote:

 	  Quote: 	
		   



 Guys



 I suppose this has been discussed before, but my laziness to search in the

 archives makes me raise this issue again.

 In the RV-10 that I am building, I am thinking in using a 12V(14V)

 electrical system, most probably based in the Nuckolls's Z-14 architecture,

 with the VP-X Pro box.



 However, when searching for the Comm radios to choose from, I found that the

 best radios, in terms of transmitting power (16W), are 28V.

 Should I consider changing all the electric system to 28V, or is it possible

 to have a 14V system and include a 14/28 voltage "converter" to feed the

 radio?



 All opinions welcome

 Regards

 Carlos



Unless you're operating in an environment where the last 1/2 mile of 
	


range matters, don't worry about it. VHF is basically line of site, & 

even a 3W handheld (with a proper external antenna) can reach the 

horizon unless you're flying at airliner altitudes. I'm too lazy to dig 

up the math, but here's a rough rule of thumb: If you want to double 

your range, multiply power by 10.



Charlie

bbradburry(at)bellsouth.n
Guest

Posted: Sat Jul 27, 2013 6:35 am Post subject: 14V or 28V

In an experimental plane, you will save a few ounces, maybe even a pound or

two in smaller wires, but you will add 10-15 pounds for the larger battery.

If you decide you should install two batteries...WOW!  You will not find any

automotive parts that are 28V.  I suggest you will need a reason better than

weight savings to go 28V.



B2



--

donjohnston

Joined: 13 Dec 2009
Posts: 231

Posted: Sat Jul 27, 2013 2:16 pm Post subject: Re: 14V or 28V

 	  bbradburry(at)bellsouth.n wrote: 	
		  In an experimental plane, you will save a few ounces, maybe even a pound or

two in smaller wires, but you will add 10-15 pounds for the larger battery.

If you decide you should install two batteries...WOW!  You will not find any

automotive parts that are 28V.  I suggest you will need a reason better than

weight savings to go 28V.-- 	




I would agree. I'm building a 28v system and the... adjustments I've had to make are a bit of a pain. If I were starting from scratch, I'd probably go with a 14v system.

henador_titzoff(at)yahoo.
Guest

Posted: Sat Jul 27, 2013 5:31 pm Post subject: 14V or 28V

Don, Bill, Carlos,



Apart from the 14V vs. 28V debate, I'd like to point out that one doesn't necessarily have to add 10-15 lbs for the "28V" battery, i.e. it isn't necessarily that much of a "larger" battery. 12V batteries have six plates, while "28V" batteries have 12 plates.  If one needs the same amount of power at the starter, an equally sized "28V" battery with smaller plates will do the job, since P = E*I.  Voltage goes up, but current goes down in  the same proportion, or slightly less since the voltage drops to the starter will sum less. In summary, same battery size, same energy density, just higher voltage with less current needed.

Enough theory, now let's look at real world numbers. I've put quotes around the 28Vs above, because 28V aircraft batteries are actually 24V, as one can see at the following link:

     http://www.concordebattery.com/allaircraftbatteries.php



Note that the Concorde CB-25 12V battery weighs 22 lbs, while the CB24-11 24V battery weighs 27 lbs. If Carlos plans his electrical system well, surely he can make up that additional 5 lb weight by using fat wires.



Henador  Titzoff





        From: donjohnston <don(at)velocity-xl.com>

 To: aeroelectric-list(at)matronics.com 

 Sent: Saturday, July 27, 2013 6:16 PM

 Subject: Re: 14V or 28V

  

 

--> AeroElectric-List message posted by: "donjohnston" <don(at)velocity-xl.com (don(at)velocity-xl.com)>

bbradburry(at)bellsouth.n wrote:

 	  Quote: 	
		   In an experimental plane, you will save a few ounces, maybe  even a pound or

 two in smaller wires, but you will add 10-15 pounds for the larger battery.

 If you decide you should install two batteries...WOW!  You will not find any

 automotive parts that are 28V.  I suggest you will need a reason better than

 weight savings to go 28V.--


	




I would agree. I'm building a 28v system and the... adjustments I've had to make are a bit of a pain. If I were starting from scratch, I'd probably go with a 14v system.





Read this topic online here:



http://forums.matronics.com/viewnbsp;  --> http://www.matronics.com/Navigator?AeroElectric-List<; http://forums.sp;            - List Contribution Web Site -

_;                         -Matt Dralle, List =========

 

 

  

 [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Sat Jul 27, 2013 7:27 pm Post subject: 14V or 28V

At 09:34 AM 7/27/2013, you wrote:

 	  Quote: 	
		  

<bbradburry(at)bellsouth.net>



In an experimental plane, you will save a few ounces, maybe even a pound or

two in smaller wires, but you will add 10-15 pounds for the larger battery.


	


   not strictly true. When going to a higher voltage system

   a battery with 1/2 the a.h. capacity has the same stored

   energy as the lower voltage battery.



 	  Quote: 	
		  If you decide you should install two batteries...WOW!  You will not find any

automotive parts that are 28V.  I suggest you will need a reason better than

weight savings to go 28V.


	


   The weight savings are pretty small . . . we did

   some calculations on it way back when here on the

   list. Not very impressive until you considered

   a sea-plane with very long + and ground leads.



   Many of the compelling reasons for 28v circulating

   in the wild are more fantasy or error than face. See

   page 12 and on in this document.



http://tinyurl.com/k9v2rfw



    A 28v battery at 1/2 capacity will not be as roubust

    to the effects of cranking events.



    Cessna went 100% 28v for manufacturing conveniences

    and before the advent of the higher efficiency, geared

    light weight starters.



    It would be interesting to see those economics

    re-evaluated but in the certified, heavy iron

    business, it's not likely to happen.



    The most compelling reason cited for 28v here on

    the list was "my engine came fitted with 28v hardware

    and I didn't what to change it out."

   Bob . . .

trigo(at)mail.telepac.pt
Guest

Posted: Sun Jul 28, 2013 3:06 am Post subject: 14V or 28V

Bob

and all



Still didn't get any answer about the second part of my initial query.

How about keeping the 14V system and using a 14/28 voltage converter to feed

the radio?



Carlos   





--

mrspudandcompany(at)veriz
Guest

Posted: Sun Jul 28, 2013 4:16 am Post subject: 14V or 28V

 	  Quote: 	
		   Still didn't get any answer about the second part of my initial query.

 How about keeping the 14V system and using a 14/28 voltage converter to 

 feed

 the radio?


	




        You could use something like this.  Just make sure that you

        size it to supply enough 24 volt power for your needs.

        This will connect to your 12 volt system and supply 24 volts

        to your radios.



        http://aconinc.com/index.php?route=product/product&path=1_12400_12402&product_id=136



        Using this would mean that there is no other mod required

        to your aircraft electrical system thus maintaining a standard

        12 volt system.



        Roger 

--



Do you have a slow PC? Try a Free scan http://www.spamfighter.com/SLOW-PCfighter?cid=sigen

henador_titzoff(at)yahoo.
Guest

Posted: Sun Jul 28, 2013 4:29 am Post subject: 14V or 28V

Carlos,

Check out this 14V to 28V converter at Aircraft Splice:

      http://www.aircraftspruce.com/catalog/elpages/lsStepUpCon.php?clickkey=87526

 

Things you might want to consider are:

Cost:  $450 plus shipping
Weight: 0.7 lbs, which is pretty low in my opinion, given it's TSO'ed

Reliability: 100K hrs MTBF, not bad
Output: 27.5V, 8 Amps or 220W, enough for your 16W transmitter power. The radio will probably pull 2.5 times that, so 40W isn't so bad and will be good for the converter's MTBF
Heatsink: may require that you mount it to a metal surface, which is no problem in your RV
Ripple: 25 mV P-P. This and the switching frequency may affect your radio's audio output and also ride on the transmission modulation. Depending on your install, your problem may be never or forever.

Seems like a lot of hassle for very little, but if you gotta have it, it may be the solution

Henador Titzoff

         From: Carlos Trigo <trigo(at)mail.telepac.pt>

 To: aeroelectric-list(at)matronics.com 

 Sent: Sunday, July 28, 2013 7:05 AM

 Subject: RE: AeroElectric-List: 14V or 28V

  

 

--> AeroElectric-List message posted by: "Carlos Trigo" <trigo(at)mail.telepac.pt (trigo(at)mail.telepac.pt)>



Bob

and all



Still didn't get any answer about the second part of my initial query.

How about keeping the 14V system and using a  14/28 voltage converter to feed

the radio?



Carlos   

--

ceengland7(at)gmail.com
Guest

Posted: Sun Jul 28, 2013 6:08 am Post subject: 14V or 28V

It will work, if you really want to do it. I've got a Garmin 430 28v 

model on the shelf that I'll install in my RV-7 (12v system) with a 

14-28v adapter. But the only reason to do that is that I got a 'deal' on 

the radio. The adapter adds weight & costs efficiency.  As I said in my 

previous response, it's unlikely that you'll be able to tell the 

difference in range between a 6 watt radio and a 16 watt radio.



Charlie



On 07/28/2013 06:05 AM, Carlos Trigo wrote:

[quote] 



 Bob

 and all



 Still didn't get any answer about the second part of my initial query.

 How about keeping the 14V system and using a 14/28 voltage converter to feed

 the radio?



 Carlos





 --

Eric M. Jones

Joined: 10 Jan 2006
Posts: 565
Location: Massachusetts

Posted: Sun Jul 28, 2013 6:52 am Post subject: Re: 14V or 28V... or 42V?

(from my Z-100 paper) Choosing a Voltage for Your Airplane Project.



Bob's Nuckolls (AeroElectric guru) often makes the point about the relative costs of using 14V automotive components, and I have to agree. If you went to buy your electrical system from the â€œ28V-Storeâ€, you'd find that most of the stuff was expensive, for certificated a/c  (remember that they certify the milk, but they certificate the cow) and the selection would not be all that large. The â€œ14V-Storeâ€ has all the bargains and selection to be sure.



In short, the advantages of 28V don't seem to warrant the added expense. Although 28V is very handy for producing the high currents needed to start big diesel truck engines, many get along fine on 14V.  Super-capacitors are also finding use in starting diesels.



Is the auto industry going to 42V? (Arguments applicable to 28V too.)



I was spreading that rumor once. More recent rumors show advantages in staying at 14V; because LED lighting systems, microprocessors, and mosfets solid-state switches, are more efficient at lower voltages, while the use of single-wire power busses makes the argument about smaller wire gauges less important for small aircraft (higher voltages still do make sense for large aircraft). The integration of the starter and alternator works fine at 14V too. 



The extinguishing of electrical-contact arcing is a difficult problem at 42V, and problems of load dump and transient voltages are much more severe. Higher voltage motors are smaller but they use smaller gauge windings too, thus the cost-per-watt of the motor goes up. A 42V system can injure or even kill mechanics and tinkerers. Trying to jump 14V and 42V vehicles can destroy the 14V vehicleâ€™s electrical system. 



Then too, 42V and 28V systems corrode faster than 14V systems. Itâ€™s a no-brainer that more volts is better from a motive-power standpoint, but many in the automotive field now say the move to 42V systems will never happen.



Big, really big aircraft use bunches of voltage buses, 12, 28,  even 120VAC, and more to accomplish their various needs.



But for the small experimental a/c, Go with 14V. Use PerihelionDesign.com CCA to reduce the Fatwire weight.

_________________
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Jul 28, 2013 8:12 am Post subject: 14V or 28V

 	  Quote: 	
		  



Big, really big aircraft use bunches of voltage buses, 12, 28,  even 

120VAC, and more to accomplish their various needs.


	


   The B-52's I cut my avionics teeth on sported 400Hz,

   208 3-phase systems for all but the lowest power

   systems and those that HAD to run on batteries for

   emergency situations.



   Getting a 400Hz system to play well required constant

   speed drives between the variable speed engine and the

   alternator that really need to run at 12,000 or 6,000

   RPM all the time.  I think the B-52 had hydraulic

   drives - a variable displacement pump plumbed to

   a variable displacement motor. A governor modulated

   the wobble plates such that for any RPM at the input

   shaft, the output shaft speed was constant.



   Nowadays, wild frequency systems are becoming more

   prevalent. This is made practical by the advent of

   high horsepower, brushless DC motors and a constellation

   of high-voltage switching technologies to go with it.

   The need for constant speed drives goes away.



   Now the large system designer can carry much greater

   flows of energy around the airplane on twisted trios.

   The frequency of the ac no longer drives rotational

   speed off the motors because the AC is rectified locally

   to relatively smooth 270VDC with the same, acceptably

   low ripple (5%) we enjoy from our 3-phase a 14v alternators.



   The high voltage ac is easier to control in solid state

   components with triacs so arcing issues associated with

   mechanical contacts goes away.



   The simple ideas are unchanged, the deck of cards has

   be reshuffled to exploit technology advances in

   high voltage semiconductors.



   DC systems on large aircraft tend to be localized,

   like the forward battery on the B787 is used for emergency

   backup in the cockpit, the mid-ships battery primarily

   used to crank an APU. In neither instance is the DC battery

   power shipped very far on wires.



   Local DC requirements are easily addressed with switchmode

   power supplies not unlike those we find in our computers

   and cell phone chargers. Pipe POWER around the airplane

   on 115/208 VAC and convert it to DC locally as needed.

   Bob . . .

jluckey(at)pacbell.net
Guest

Posted: Mon Jul 29, 2013 9:06 am Post subject: 14V or 28V

You have to be careful when selecting power converters of this type.  

Be aware of the power requirements.  If the radio in question only draws 2 amps at transmit then that's 48 watts of power, P = IE (watts = amps x volts) that the converter must deliver when you key the mic.  The one referenced is only 13 watts and would be inadequate.

        From: R. curtis <mrspudandcompany(at)verizon.net>

 To: aeroelectric-list(at)matronics.com 

 Sent: Sunday, July 28, 2013 5:15 AM

 Subject: Re: 14V or 28V

 --> AeroElectric-List message posted by: "R. curtis" <mrspudandcompany(at)verizon.net (mrspudandcompany(at)verizon.net)>

 	  Quote: 	
		   Still didn't get any answer about the second part of my initial query.

 How about keeping the 14V system and using a 14/28 voltage converter to feed

 the radio?

       You could use something like this.  Just make sure that you

       size it to supply enough 24 volt power for your needs.

       This will connect to your 12 volt system and supply 24 volts

       to your radios.

       http://aconinc.com/index.php?route=product/product&path=1_12400_12402&product_id=136

       Using this would mean that there is no other mod required

       to your aircraft electrical system thus  maintaining a standard

       12 volt system.

       Roger 

--

Do you have a slow PC? Try a Free scan http://www.spamfighter.com/SLOW-PCfighter?cid=sigen

trigo(at)mail.telepac.pt
Guest

Posted: Mon Jul 29, 2013 9:23 am Post subject: 14V or 28V

Jeff

 

Thanks for calling my attention.

In that case, I suppose the adequate should be this one

 

http://aconinc.com/index.php?route=product/product&path=1_12400_12406&product_id=436

 

or this one 

 

http://aconinc.com/index.php?route=product/product&path=1_12800_12807&product_id=531

 

Is that so?

Carlos 

 

 

De: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] Em nome de Jeff Luckey

Enviada: 29 de julho de 2013 18:04

Para: aeroelectric-list(at)matronics.com

Assunto: Re: 14V or 28V

 

You have to be careful when selecting power converters of this type.  



Be aware of the power requirements.  If the radio in question only draws 2 amps at transmit then that's 48 watts of power, P = IE (watts = amps x volts) that the converter must deliver when you key the mic.  The one referenced is only 13 watts and would be inadequate.

 

From: R. curtis <mrspudandcompany(at)verizon.net (mrspudandcompany(at)verizon.net)>

To: aeroelectric-list(at)matronics.com (aeroelectric-list(at)matronics.com) 

Sent: Sunday, July 28, 2013 5:15 AM

Subject: Re: 14V or 28V

--> AeroElectric-List message posted by: "R. curtis" <mrspudandcompany(at)verizon.net (mrspudandcompany(at)verizon.net)>

 	  Quote: 	
		   Still didn't get any answer about the second part of my initial query.

 How about keeping the 14V system and using a 14/28 voltage converter to feed

 the radio?


	




      You could use something like this.  Just make sure that you

      size it to supply enough 24 volt power for your needs.

      This will connect to your 12 volt system and supply 24 volts

      to your radios.



      http://aconinc.com/index.php?route=product/product&path=1_12400_12402&product_id=136



      Using this would mean that there is no other mod required

      to your aircraft electrical system thus maintaining a standard

      12 volt system.



      Roger 



--



Do you have a slow PC? Try a Free scan http://www.spamfighter.com/SLOW-PCfighter?cid=sigen

<br                     ========================

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  [quote][b]

Eric M. Jones

Joined: 10 Jan 2006
Posts: 565
Location: Massachusetts

Posted: Mon Jul 29, 2013 9:37 am Post subject: Re: 14V or 28V

BTW: The presumption that a 28V radio has greater transmitting power than a 12V radio is, in principle, untrue.

_________________
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones(at)charter.net

jluckey(at)pacbell.net
Guest

Posted: Mon Jul 29, 2013 9:56 am Post subject: 14V or 28V

Carlos,



You should start with the spec sheet of the radio that you want to use to determine its current draw.  Then you can use the formula I provided to calc the required power.  I would then select a power converter that gives you a significant safety margin of power; perhaps at least 20 percent greater power than your calculation indicates.



Let's hope someone on this List has done this before and can recommend a device that they have used successfully.





        From: Carlos Trigo  <trigo(at)mail.telepac.pt>

 To: aeroelectric-list(at)matronics.com 

 Sent: Monday, July 29, 2013 10:21 AM

 Subject: RE: 14V or 28V

  

 

Jeff

  

Thanks for calling my attention.

In that case, I suppose the adequate should be this one

  

http://aconinc.com/index.php?route=product/product&path=1_12400_12406&product_id=436

  

or this one 

  

http://aconinc.com/index.php?route=product/product&path=1_12800_12807&product_id=531

  

Is that so?

Carlos 

  

  

De: owner-aeroelectric-list-server(at)matronics.com [mailto:owner-aeroelectric-list-server(at)matronics.com] Em nome de Jeff Luckey

Enviada: 29 de julho de 2013 18:04

Para: aeroelectric-list(at)matronics.com

Assunto: Re: 14V or 28V

  

You have to be careful when selecting power converters of this type.   



Be aware of the power requirements.  If the radio in question only draws 2 amps at transmit then that's 48 watts of power, P = IE (watts = amps x volts) that the converter must deliver when you key the mic.  The one referenced is only 13 watts and would be inadequate.

  

From: R. curtis <mrspudandcompany(at)verizon.net (mrspudandcompany(at)verizon.net)>

To: aeroelectric-list(at)matronics.com (aeroelectric-list(at)matronics.com) 

Sent: Sunday, July 28, 2013 5:15 AM

Subject: Re: AeroElectric-List: 14V or 28V

--> AeroElectric-List message posted by: "R. curtis" <mrspudandcompany(at)verizon.net (mrspudandcompany(at)verizon.net)>

 	  Quote: 	
		   Still didn't get any answer about the second part of my initial query.

 How about keeping the 14V system and using a 14/28 voltage converter to feed

 the  radio?


	




      You could use something like this.  Just make sure that you

      size it to supply enough 24 volt power for your needs.

      This will connect to your 12 volt system and supply 24 volts

      to your radios.



      http://aconinc.com/index.php?route=product/product&path=1_12400_12402&product_id=136



      Using this would mean that there is no other mod required

      to your aircraft electrical system thus maintaining a standard

      12 volt system.



      Roger 



--



Do you have a slow PC? Try a Free scan http://www.spamfighter.com/SLOW-PCfighter?cid=sigen

<br                     ========================



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 [quote][b]

trigo(at)mail.telepac.pt
Guest

Posted: Mon Jul 29, 2013 10:08 am Post subject: 14V or 28V

Eric



Would you please elaborate a little bit on your opinion?

But do it for an electron-idiot guy, please...



Carlos



-----Mensagem original-----

De: owner-aeroelectric-list-server(at)matronics.com

[mailto:owner-aeroelectric-list-server(at)matronics.com] Em nome de Eric M.

Jones

Enviada: 29 de julho de 2013 18:38

Para: aeroelectric-list(at)matronics.com

Assunto: Re: 14V or 28V




--> <emjones(at)charter.net>



BTW: The presumption that a 28V radio has greater transmitting power than a

12V radio is, in principle, untrue.



--------

Eric M. Jones

www.PerihelionDesign.com

113 Brentwood Drive

Southbridge, MA 01550

(508) 764-2072

emjones(at)charter.net





Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=405583#405583

deej(at)deej.net
Guest

Posted: Mon Jul 29, 2013 10:41 am Post subject: 14V or 28V

 	  Quote: 	
		   Would you please elaborate a little bit on your opinion?

 But do it for an electron-idiot guy, please...


	




I'm not Eric, but I'll chime in.  VHF radio transmissions are line of

site.  For the most part, if you can see it, you can "hear" it via radio.



Several years ago I climbed to the top of a mountain which was about 1

mile ASL.  A friend of mine was ~80 miles away in a direct line, on the

ground at maybe 200 ASL.  We both had handheld radios, and were talking

to each other.  He was using 1/2 of a watt, I was using 1/4 of a watt

(the lowest power setting of the radios).  There was barely any

discernible difference between 5 watts (the maximum setting), and the

low power settings that we were using.



In general, for the typical distances that we are communicating in our

airplanes, combined with the height above ground, it just doesn't matter

if the radio is 8 watts or 16 watts.  The signal is only going to go as

far as line of site under normal conditions (ie, no weird atmospheric

"skip" happening).



In other words, under typical circumstances, you are not going to be

transmitting any farther using 16 watts than you are at 8 watts.



-Dj

-- 

Dj Merrill - N1JOV - VP EAA Chapter 87

Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/

Glastar Flyer N866RH - http://deej.net/glastar/

tim2542(at)sbcglobal.net
Guest

Posted: Mon Jul 29, 2013 12:15 pm Post subject: 14V or 28V

Not arguing with that, but I believe the 430AW model is 28 volts only and is the one with the 16 watt transmitter. 

Tim



Sent from my iPad



On Jul 29, 2013, at 11:37 AM, "Eric M. Jones" <emjones(at)charter.net> wrote:



 	  Quote: 	
		   

 

 BTW: The presumption that a 28V radio has greater transmitting power than a 12V radio is, in principle, untrue.

 

 --------

 Eric M. Jones

 www.PerihelionDesign.com

 113 Brentwood Drive

 Southbridge, MA 01550

 (508) 764-2072

 emjones(at)charter.net

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=405583#405583

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