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[manyquestions]

I want to run the video sender/receiver portably, so that will require building some battery packs. So I have some questions to help me decide how to do this.

1. First, if I order the new sender/receiver, will I get the gray saucer shaped units (VK82a?) or the black non-circular ones? What are the dimensions of the units I'll get? Is there any difference between the appearance of the sender and the receiver (they appear the same in the pictures)?

2. What is the power consumption (in milliamps) of the sender and the receiver? I know the voltage is stated at 12V, but at what voltage range will the units operate? What type of DC plug do the units accept? I believe the standard for 12V DC is the 5.5mm x 2.1mm plug, but it would help to know ahead of time.

3. I'm considering 10 rechargable AA batteries for each of the sender and receiver. What kind of battery life can I expect?

Thank you
manyquestions

[HA Dave]

I want to run the video sender/receiver portably, so that will require building some battery packs. So I have some questions to help me decide how to do this.

What is the power consumption (in milliamps)

Power consumption, 400ma

Could this be quick and easy enough?

A automotive starter, a cheap 12V to 120 Volt AC converter. Construction time, one minute.

[manyquestions]

Actually, I was thinking of using something like the AC103 battery box, which holds 10 AA batteries. Using rechargeable batteries should give me about 12V. It has a 5.5mm x 2.1 mm plug, which may or may not work on the sender/receiver. If it's not correct, I'll probably need some sort of adapter.

I was told by technical support that they drew 300 mA, but they didn't seem sure, so I posted here. I purchased them anyway because they're cheap enough not to put a dent in my wallet if I'm wrong. But I'd like to be able to make the calculations ahead of time so that I can buy everything at the same time to prevent delays.

By my calculations, assuming 2400 mAh batteries, I should get about 8 hours with 300 mA and 6 hours with 400 mA (probably less in reality). I'd prefer the 8 hours but 6 hours should be okay. Is there any difference in the power consumption of the receiver and sender, or are they both 400 mA?

DC to AC to DC is okay but it's probably not going to be very efficient in terms of maximizing battery life, and will probably take up more space than I want to. The AC103 has a very small footprint (surprisingly small).

Am I going about this the right way? Any flaws in what I'm saying?

Thanks
manyquestions

[HA Dave]

Is there any difference in the power consumption of the receiver and sender, or are they both 400 mA?

Sender 400, receiver 300 (I hadn't realized that)

Am I going about this the right way? Any flaws in what I'm saying?

Sounds to me like you've got a plan.

[TakeTheActive]

A automotive starter, a cheap 12V to 120 Volt AC converter. Construction time, one minute.

...DC to AC to DC is okay but it's probably not going to be very efficient in terms of maximizing battery life, and will probably take up more space than I want to. The AC103 has a very small footprint (surprisingly small).

Dave_x10_L,

How much power is WASTED by going from DC-to-AC-to-DC?

I want to run the video sender/receiver portably, so that will require building some battery packs...

Why?

3. I'm considering 10 rechargable AA batteries for each of the sender and receiver. What kind of battery life can I expect?

Let's change this question to "How much RUNNING TIME do you require?"

You can get a nice 12VDC 7AH Lead Acid cell (the kind used in UPSs) for under $10, but it's a HEAVY sucker. Over 25 years ago, I REFUSED to pay the prices for 'custom' NiCd cells for my VHS video recorder/camera combo, so I built a two 6VDC Lead Acid pack and "installed it" in the accessory pocket of the recorder's case. When we went to air shows (and needed EVEN LONGER CAPACITY), I dragged along a 12VDC car battery and my son's "Little Red Wagon".

More details, please...

[HA Dave]

A automotive starter, a cheap 12V to 120 Volt AC converter. Construction time, one minute.

...DC to AC to DC is okay but it's probably not going to be very efficient in terms of maximizing battery life, and will probably take up more space than I want to. The AC103 has a very small footprint (surprisingly small).

Dave_x10_L,

How much power is WASTED by going from DC-to-AC-to-DC?

I haven't a clue! However...... I do know last power outage we had I used the same car starter and DC/AC converter to run a 1.3 watt LED bulb for HOURS. Of course..... if I wanted to run a 12v DC device direct from the car starter..... how hard could that be!

[manyquestions]

I don't know specifically how to calculate the efficiency in going from DC to AC to DC, but some experiments I've done have indicated it's not ideal, and you'd require a much larger battery than if you were able to just use a DC source directly.

One thing I did try was to power my camcorder with a battery pack with more energy capacity than it's normal battery. I did DC to AC to DC. I got significantly less run time than with it's normal battery and it was less reliable, cutting in and out often with some buzzing sounds (toward the end of the experiment). I think those DC to AC inverters are not very efficient and they generate a lot of heat. So, why do that when it's easy to find a battery pack that will do it without any need for conversion to AC?

When I said build a battery pack, what I meant was just buy the appropriate battery holder, find the necessary plug adapters, load it up with batteries, and I'm ready to go.

That brings me to one of my questions. What type of plug do the senders/receivers use? Surely, someone must know.