power consumption

[Tibuck19]

What that means is that the maximum current it can supply is 100mA, not that it always consumes 100mA. The "fixed output" refers to the voltage.

That is what I was thinking, I just wanted to make sure, How long does your
minipulse battery charge last for ?

[homefire]

Again run your battery through a Amp meter to the detector and determine what it's pulling. Divide that by your battery amp hour rating and you will get a Idea on how long the battery should be able to perform.

[Qiaozhi]

That is what I was thinking, I just wanted to make sure, How long does your
minipulse battery charge last for ?

The current consumption will depend on the coil parameters, the TX pulse width, and the TX pulse rate.
The MPP does not employ flat-topping of the coil current in the default design, which means that the TX pulse current could vary somewhat between different coils.
If (as Homefire has suggested) you measure the average current being consumed by the whole circuit, you can get an estimate of the potential detecting time. The calculated value will be close to the actual value. For example, if the measured value is 200mA, and you battery capacity is 2000mAh, then you can expect 10 hours of detecting time.

With the default MPP settings of 58us TX pulse width, 1000pps TX rate, Rs = 3R3, L=300uH, and Rl = 1R4; the coil current will rise to about 1.5A, with an average current of aroundt 88mA. In this case, a 2000mA battery pack will last > 22 hours. In practice the coil current will be lower than 1.5A due to the MOSFET and series diode resistances, but other parts of the MPP's circuit will consume additional current. On balance though, these two factors tend to cancel one another.

Even if you increased the TX pulse width so that the coil current flat-tops, the average consumption would only increase to 145mA, with a detecting time of > 13 hours. If you're only getting 3 hours, then I would suspect the battery pack is failing.

[Tibuck19]

The current consumption will depend on the coil parameters, the TX pulse width, and the TX pulse rate.
The MPP does not employ flat-topping of the coil current in the default design, which means that the TX pulse current could vary somewhat between different coils.
If (as Homefire has suggested) you measure the average current being consumed by the whole circuit, you can get an estimate of the potential detecting time. The calculated value will be close to the actual value. For example, if the measured value is 200mA, and you battery capacity is 2000mAh, then you can expect 10 hours of detecting time.

With the default MPP settings of 58us TX pulse width, 1000pps TX rate, Rs = 3R3, L=300uH, and Rl = 1R4; the coil current will rise to about 1.5A, with an average current of aroundt 88mA. In this case, a 2000mA battery pack will last > 22 hours. In practice the coil current will be lower than 1.5A due to the MOSFET and series diode resistances, but other parts of the MPP's circuit will consume additional current. On balance though, these two factors tend to cancel one another.

Even if you increased the TX pulse width so that the coil current flat-tops, the average consumption would only increase to 145mA, with a detecting time of > 13 hours. If you're only getting 3 hours, then I would suspect the battery pack is failing.

I understand homefire, what he means by finding out the mA it uses,I did that, and I am getting 0.20 which I believe it means 200ma , which should give me at least 10 good hours, Which is why I was asking how long yours run an average to determine is its my MMP or my Batteries , we all know im rather new compared to most of you, and I do find myself second and third guessing myself lol . Thank you for the in-depth reply which helps me a great deal.

[Qiaozhi]

I understand homefire, what he means by finding out the mA it uses,I did that, and I am getting 0.20 which I believe it means 200ma , which should give me at least 10 good hours, Which is why I was asking how long yours run an average to determine is its my MMP or my Batteries , we all know im rather new compared to most of you, and I do find myself second and third guessing myself lol . Thank you for the in-depth reply which helps me a great deal.

Have you made some changes to the default design? If so, what are they?

[Tibuck19]

I only real changes I have made is replaced R-7 and are R-8 with trimmer pots. which if I recall right R7 was set at 2K8 and not at 1K8 but I put it back to it original values and charged up new batteries and will try that out