Getting main armament and headlight working

Discuss the good old Heng Long electronics here, whether its mods on them or anything else, it goes here!
User avatar
tankme
Warrant Officer 1st Class
Posts: 1985
Joined: Tue Oct 31, 2017 3:51 pm
Location: Elgin, TX
Contact:

Re: Getting main armament and headlight working

Post by tankme »

Now I will say that I don't use resistors with my HL board as they are supposed to be regulated for the LED voltages. I don't recall seeing any resistors on the Taigen board installs, but those are removed pretty much right after I buy them. I've primarily needed resistors with my Open Panzer TCB boards as they deliver full board voltage to the LED slots. I smoked a bunch of LEDs on my HL ZTZ-99. I guess I should've read the documentation before wiring them in... :)
Derek
Too many project builds to list...
User avatar
flyingbogey
Recruit
Posts: 21
Joined: Wed Aug 04, 2021 11:58 am
Location: London UK

Re: Getting main armament and headlight working

Post by flyingbogey »

The resistor value can be easily worked out from
V=IR
Volts = Current (amps) x Resistance (ohms).

With a 7.4 Volt battery
if you want 2 V across your diode with a current of 25mA, 0.025A This will depend on the spec of the diode
then as the diode and resistor are in series, calculate the voltage across the resistor thus:
Battery voltage - voltage across diode.
so
7.4 - 2 = 5.4v

Then the resistance, because you want 25mA, 0.025A is

5.4 = 0.025 x resistor

rearranging, divide both sides by 0.025
5.4/0.025 = resistor = 216 Ohms.

216Ohms is a nonstandard value, so round up to the nearest, 220Ohms.

Hope I'm not teaching anyone to suck eggs...
Last edited by flyingbogey on Sun May 08, 2022 10:19 am, edited 1 time in total.
“I'd far rather be happy than right any day.” Douglas Adams

HL Tiger...WIP
HL Pz IV AusfF1, Finishing touches
Robbe: Type VII B
Billings: Thor Coastguard
Partial scratch: Akula Class Sub
Rebuild: Vosper Perkasa
User avatar
Son of a gun-ner
Lieutenant-Colonel
Posts: 6931
Joined: Sun May 07, 2017 8:49 pm
Location: Surrey UK

Re: Getting main armament and headlight working

Post by Son of a gun-ner »

flyingbogey wrote:Hope I'm not teaching anyone to suck eggs...
Egg sucking is good :thumbup:
Due to the various levels of knowledge of our members, it is always best to have as much useful information as possible within a subject.
Also, for some members, its been a long time since they left school, and therefore easy to forget things they haven't needed to remember.
To conclude, if you notice your known relevant information hasn't been mentioned by anyone else, never hold back from sharing, no matter how obvious it seems to you.
Mick - The grit in the underpants of life!
And always happy to spare the bytes

TOTM needs YOU :thumbup: support YOUR TOTM competition, I'm doing my part, are YOU?
User avatar
flyingbogey
Recruit
Posts: 21
Joined: Wed Aug 04, 2021 11:58 am
Location: London UK

Re: Getting main armament and headlight working

Post by flyingbogey »

I wonder then if a section, within the electronics board, for such gems would be a handy resource?
“I'd far rather be happy than right any day.” Douglas Adams

HL Tiger...WIP
HL Pz IV AusfF1, Finishing touches
Robbe: Type VII B
Billings: Thor Coastguard
Partial scratch: Akula Class Sub
Rebuild: Vosper Perkasa
User avatar
Son of a gun-ner
Lieutenant-Colonel
Posts: 6931
Joined: Sun May 07, 2017 8:49 pm
Location: Surrey UK

Re: Getting main armament and headlight working

Post by Son of a gun-ner »

flyingbogey wrote:I wonder then if a section, within the electronics board, for such gems would be a handy resource?
I guess it would. Just needs someone knowledgeable who's willing to spend the time writing it all out in a new thread titled appropriately.
Then one of us in the forum team can make it a permanent sticky.
Mick - The grit in the underpants of life!
And always happy to spare the bytes

TOTM needs YOU :thumbup: support YOUR TOTM competition, I'm doing my part, are YOU?
User avatar
flyingbogey
Recruit
Posts: 21
Joined: Wed Aug 04, 2021 11:58 am
Location: London UK

Re: Getting main armament and headlight working

Post by flyingbogey »

Ah yes time.. LOl.
I will try and scribble something. Working nights soon so that will give me something to do. :haha:
“I'd far rather be happy than right any day.” Douglas Adams

HL Tiger...WIP
HL Pz IV AusfF1, Finishing touches
Robbe: Type VII B
Billings: Thor Coastguard
Partial scratch: Akula Class Sub
Rebuild: Vosper Perkasa
User avatar
Son of a gun-ner
Lieutenant-Colonel
Posts: 6931
Joined: Sun May 07, 2017 8:49 pm
Location: Surrey UK

Re: Getting main armament and headlight working

Post by Son of a gun-ner »

flyingbogey wrote:Ah yes time.. LOl.
I will try and scribble something. Working nights soon so that will give me something to do. :haha:
The hardest part would be writing it for anyone to understand, what may seem obvious isn't always so.
Well, if you do undertake this task, it will no doubt be very appreciated :thumbup:
We do have a few nuggets of electronics information scattered around the forum, it would be excellent to have such knowledge in one place and not lost pages down through time.
Mick - The grit in the underpants of life!
And always happy to spare the bytes

TOTM needs YOU :thumbup: support YOUR TOTM competition, I'm doing my part, are YOU?
User avatar
Herr Dr. Professor
Lieutenant
Posts: 3621
Joined: Mon Apr 22, 2019 10:48 pm
Location: Southern Wisconsin USA

Re: Getting main armament and headlight working

Post by Herr Dr. Professor »

Yes, this is a waggish comment, but still with sincere respect for you electronics wizards.

"The hardest part would be writing it for anyone to understand."

SOG, you got that right! I encountered the term MOSFET today. Curious as always, I found https://www.youtube.com/watch?v=Bfvyj88Hs_o. :crazy:
Post Reply

Return to “Heng Long”