Threshold Pot doesn't work

[h9361]

IRF840 is fine. It's a little better than the IRF740.

Thank you dear Carl.
Unfortunately, weather condition of my city is high humidity and rainy. So i'm going to use resin for my HH PCB.
As you know, Q3 and its damping resistor heat up during operation.
Do you think it will not couse any problem for Q3 and the resistor if i cover them with resin?!
For exp, Does the resin increase their heat and eventually cause them to burn?

[Carl-NC]

Yes, resin will reduce thermal convection and cause it to get hotter.
Edit: unless you use a thermally conductive epoxy.
Also be aware that some epoxies can also have a dielectric effect and may slow down the coil decay.

[h9361]

Thanks.
Some of friends use stone glue, i think it's strange. Have you heard anything about this?

[Carl-NC]

Never heard of it.

[waltr]

The 12V regular should work IF a 7660A is used.

The 3.6V per LiIo cell is the Nominal Voltage. At full charge they are 4.2V per cell so 16.8V for 4S.
This does waste power since the Voltage drop across the regulator times the current equals power as heat.

I use a 3S LiPo battery on my HH2. 12.6V at full charge, 10.8 discharged but indicate empty battery at 11V.

On your MOSFET question.
It has a higher Voltage but lower current (8A instead of 10A). 8A will be enough.

The other specs are very similar so the IRF840 should work fine.

[h9361]

The 12V regular should work IF a 7660A is used.

The 3.6V per LiIo cell is the Nominal Voltage. At full charge they are 4.2V per cell so 16.8V for 4S.
This does waste power since the Voltage drop across the regulator times the current equals power as heat.

I use a 3S LiPo battery on my HH2. 12.6V at full charge, 10.8 discharged but indicate empty battery at 11V.

On your MOSFET question.
It has a higher Voltage but lower current (8A instead of 10A). 8A will be enough.

The other specs are very similar so the IRF840 should work fine.

Very thanks dear Walter for your tips.
For keeping more charging, i'm going to use 4s but one of them is as parallel. In this case, we can remove 12V regular and keep more charge for more duration.
Please see attached, do you think it's OK?

[Carl-NC]

The one parallel battery won't make any difference in overall battery life.

[h9361]

Hello
Dear Carl
I hope you are passing good days.
I have a question about battery, do you think we have a ampere limitation for choosing battery?
As you know, can i use 10000 mAh battery for my HHD?!
Thanks.

[Carl-NC]

I don't understand the question. Higher mAh will work just fine but about the only practical benefit will be longer run time.

[h9361]

Hello
Dear Carl
I have a question about rainy day (completely ground saturated by rain water).
I tested my HHD over a Lawn land in two different days with the same THD and Delay position (approximately 20-25 us) :
1- A sunny day and ground was dry
2- A rainy day and ground was completely wet

Result 1: HHD was very nice and ground completely eliminated, while i could set THD over a pit .. pit.
Result 2: HHD can't eliminate ground in the same position of THD. So i have to decrease THD in silence, finally i could eliminate ground, but my depth was significantly decreased.

My question, do you think it's normal the problem (Muddy ground)?
Thanks.

[Carl-NC]

Has the ground been fertilized a lot? That will raise the saline content and make it reactive when wet but not dry.

[h9361]

Thanks, the ground is a natural in middle of Jungle.

[h9361]

Hello
Dear Carl
I have a question about Pulse Width (R46). As you told, it's 3us-50us. Do you think it's possible to change it to 1 or 2 us - 50us?!

[Carl-NC]

Reduce R46a.

[h9361]

Hello
Dear Carl
I hope you are passing good days.
I have a question about output audio. Do you have any suggestion to amplify more for output audio?
Now, i'm using 150R speaker, but i think its maximum volume is still low and it needs to be amplified. Because the level volume is low in open space.
Thanks.