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[Circlip]

Can't imagine any "British" manufacturer attempting to make and sell the one shown for a fiver let alone 79 pence.


 Regards  Ian.

[dodgy geezer]

Can't imagine any "British" manufacturer attempting to make and sell the one shown for a fiver let alone 79 pence.


 Regards  Ian.

Loss leader rather than profitable product. And I believe that there is extensive cross-subsidy by the Chinese state. Fighting and winning an economic war is cheaper and less damaging than a military one...

[dodgy geezer]

I've read recent posts a bit more carefully now.
  I have not ever tried diodes to see the effect. If I was curious enough I'd restrict my tests to anti-parallel pairs of rectifier diodes (A1 to K2, K1 to A2) and suppress each pair with 1 to 10nF ceramic disc caps. Google "soft-recovery + diode" . That connection makes individual 1-volt bi-directional droppers.
I'm open minded but think you'd eventually change tack if you needed to improve lower end control.  ............

I used diode droppers to vary the speeds of the pair of radar dishes on my OSA boat - they worked very well there. But an ESC output is a different kettle of fish...


 

I think you will find dropper diodes are worse than resistors in that they will make control more "woolly" like 50 Hz escs and 8 position bobs boards. ......................... You'll see a 1s Lipo forward only dual esc on Ebay. I wonder if there are fwd/ rise escs in 1s. I think there are sub assemblies, otherwise half finished escs, in 1s.
You get mini servos and receivers optimised at 1s. In theory, you can bond two gears of the common ~ 300:1 ratio in a servo to get one in the tens. I have never attempted that and think there is a high enough chance that voltage dropping can be bettered if results disappoint.
..................

I seem to specialise in small light balsa boats, and there are a host of issues associated with those. The scale effect limits realism on a pond with ripples, and 5v logic forces the use of heavy batteries - I tend to avoid LiPos because of maintenance considerations.  In practice, when you get to small sizes, 'all or nothing' motor power can be quite acceptable.
I bought a couple of these items recently - https://www.ebay.co.uk/itm/404541116079?var=674530982752   We shall see what they are like. Having no BEC is advantageous for dual use...

[HMS Invisible]

I used diode droppers to vary the speeds of the pair of radar dishes on my OSA boat - they worked very well there. But an ESC output is a different kettle of fish...

On the verge of picking nits, inductive reactance, pwm frequency x motor inductance.
I'm glad you get it and your last Ebay link is very much along the lines of what I think fits your aim.
I could put last nights ramble in another way for casual onlookers:
Diodes or resistors + pwm chopping esc + resistive load ( grain of wheat bulb) would be okay. And yes, radar motor preset at a set speed is okay with a diode. But again, diodes and resistors will magnify speed changes with a change in load friction (also temperature!)

I seem to specialise in small light balsa boats, and there are a host of issues associated with those. The scale effect limits realism on a pond with ripples, and 5v logic forces the use of heavy batteries - I tend to avoid LiPos because of maintenance considerations.  In practice, when you get to small sizes, 'all or nothing' motor power can be quite acceptable.

I followed and understood the kit project's focus and have commented on other builds in the past.

I bought a couple of these items recently - https://www.ebay.co.uk/itm/404541116079?var=674530982752   We shall see what they are like. Having no BEC is advantageous for dual use...

I think you need to change your perspective on single cell 18650 or 21700 or discarded vapes.
Look at the trend for torches, bike lights, battery bank and all these 1s powered doodahs you have that charge from USB. So much is migrating to Lipo. If your project was a profitable consumer venture I would say you have a massive blind spot. The single power source works well with low resistance chemistry as with Lipo. I've said before and will do so again. Clip a Towerpro voltage bargraph on an installation. It shows a NimH battery out of peak condition. I suggest you revisit this post in four years when Kamala Harris is...whatever.

[dodgy geezer]

You are right on several points, which I would like to discuss - but I have a lot of work on and can only come back after 17:00 ...   

[dodgy geezer]

I followed and understood the kit project's focus and have commented on other builds in the past.

I didn't know anyone followed them!  Sorry for not putting new plans out - I have been so busy with other things. But I have not ben completely idle. for example, see below - a modern corvette being built to see if a full-sized model (36") could be made using the EeZeBilt style - powered by two water jets, so a big dual esc would come in useful for that (a shot of a jet  is included. and a Surfury-like hull designed to be really simple to make...still needs to be tested since it might porpoise...

I think you need to change your perspective on single cell 18650 or 21700 or discarded vapes.
Look at the trend for torches, bike lights, battery bank and all these 1s powered doodahs you have that charge from USB. So much is migrating to Lipo. If your project was a profitable consumer venture I would say you have a massive blind spot.

You are right about the small lipos. I was impressed at how long a small toy helicopter battery held charge for after being left for years. And this size would make adding radios to the original KeilKraft boats much easier. But can you really run a motor. esc. Rx and servo off one of these?

[roycv]

Hi all, I have been using the single esc version for several years they work well, I do not expect that the alleged 10 amps to be accurate.  I expect a maximum of 4 amps and they always work for me. 
I switch on with Tx lever in neutral and then take the Tx  lever to Max,  The esc beeps with red light on and the low hum of the repetition frequency of 2Khtz.
On the units I have there is a switch which turns on (or off) the braking function.  If you leave it on, the reverse takes a short moment before going into reverse, as you would expect.
I also have a tiny mixer unit which drives 2 separate esc's.  Rather than pull a red wire from one of the esc's I use a servo extension lead in between and cut the wire in the lead. 

With the single wire from the mixer which goes into the rx mixer rudder socket, it means that the rudder has no socket to operate from.
 If I want to operate the rudder as well, then I use a Y lead with single end in the receiver.  This is for a future build where I need the rudder but not the electric motor.
regards
Roy
 

[HMS Invisible]

What happened there?

[HMS Invisible]

I didn't know anyone followed them!  Sorry for not putting new plans out - I have been so busy with other things. But I have not ben completely idle. for example, see below - a modern corvette being built to see if a full-sized model (36") could be made using the EeZeBilt style - powered by two water jets, so a big dual esc would come in useful for that (a shot of a jet  is included. and a Surfury-like hull designed to be really simple to make...still needs to be tested since it might porpoise...

I mean years after getting my attention I'm still trying to complete the EeZeBilt jigsaw picture with only your forum posts to go by. 
During setup times at a particular trade show I could have a blether with Adam of Mountfleet, Carlmt, Flundle and several others whose names and company names escapes me. 
There's a reason and a story behind all their effort and expense invested.

You are right about the small lipos. I was impressed at how long a small toy helicopter battery held charge for after being left for years. And this size would make adding radios to the original KeilKraft boats much easier. But can you really run a motor. esc. Rx and servo off one of these?

Self discharge is negligible. You can use cellsuply.co.uk as a data resource link for premium vented cells in 18650 and 21700.
So there are 20c,30c,50c RC packs and the vented cylinder and prism shaped cells.
They can be compared against cells from decommissioned high power ebike batteries, NiCD, NiMH, Pb and  discarded vape Lipo. You compare performance. Don't rely on my words and ignore any utterances about batteries from a technically illiterate fanboys.
If you do the bench top tests yourself by a 4 button multi charger then you and your social circle become resistant to a financial mugging by old battery tech at premium price. 
And if you scope or monitor voltage with a led bargraph by yourself then you understand why a discharged lipo works a circuit where a charged NiMH that hasn't been pulse charged keeps triggering brown outs or under voltage protection. Dendrite forms and cell resistance rises above the datasheet figure even when it is new.
You could nip into poundland for two 2Ah pen bank or buy two and solder a connector to the 18650 cell then rob the charge circuit to fit it onto a rechargeable lipo from a discarded disposable vape.

I'd dial back the voltage from a power supply or the tiny 3amp 3-24v modules to see when an esc drops out. I'd also look at the circuit.
 Those 50p modules are the best performing devices to set radar speed of a bare motor.

I've seen Youtube footage of brushless jet boats and that's the way to do them.

[dodgy geezer]

I mean years after getting my attention I'm still trying to complete the EeZeBilt jigsaw picture with only your forum posts to go by.

Not sure what you mean by this? `
There is not much data out there about EeZeBilts, or the Keil Kraft company generally, which is rather surprising. Bassett-Lowke, for instance, has a lot of documentation  available, and I would rate Keil Kraft as just as influential on the UK model scene.
A continual problem for boats, compared to aircraft, is that aircraft plans are comprehensive and readily collectible - Outer Zone have done a fine job. But commercial model boat kits often had 'assembly notes' rather than plans, and then they might have used fibreglass/plastic hulls, both techniques making it very hard to 'save' the kit data...

[HMS Invisible]

You are proving the point I was trying to make.
I'm sixty years old and started making models at eight. So I know Keilkraft and could have stopped you trying to tell me that part.
The two points I was trying to make last night is, firstly, I don't know the E.....t raison d'etre as I missed the memo, so to speak. Secondly, I can't learn as fast by reading an open forum as  I do in a friendly inquiring blether. Everything I needed to know about 3d printing came from Carl in a 5 minute chinwag.
I can wait until next summer or the one after that to meet up.

Since my battles with the editor last night I've organised my phone's photo gallery. My posts will have more relevant photos and a tenth of the one finger typing that amounts to nought, most times.

[HMS Invisible]

 Here is the 18 by 12mm module, costing ~50p which is great for radar motors and led circuits.
It shows where I've replaced the variable resistor with 39kΩ for fixed 5.1 volt.

The second photo is where I snipped out a 7805 2p bec from an 18 amp dual esc.
The point of the exercise is to rectify one of the two achilles heels of  Chinese escs.

....and "british" are the same inside, Circlip.
... use the same "wun hung lo" 5p components instead of premiem grade Texas,SGS, IR etc.
"British", unlike Chinese would pay to give them away to readers.
Dissolve in an airtight tub of dichloromethane for two weeks and you see they are not so different apart from the Orientals, whom are more generous with the output fets.

[HMS Invisible]

Small rechargeable lipo for small and light boat.
See https://m.youtube.com/watch?v=7VSwMfDANMY for Big Clive's explanation of what is inside the cheapest high street powerbank.
The photos should be self evident.
In order,
The charge management circuits removed from banks.
18650 and small disposable vape cell side by side.
Remove both vape end caps and push the battery out the bottom

The poundland powerbank cells are 2,200mAh but not premium cells like the green LG 13Wh cell you'd use to make an ebike battery. They are 2,200mAh but internal resistance is higher than in the wholesale LG,Sony,Sanyo,Samsung which come in hundred boxes, all at the same charge. However they are more than up to your requirement.

[HMS Invisible]

I was knocked of track while another reply came before I uploaded and captioned this photo . It was to encourage you to do a continuty test to make sure either white or yellow didn't short against 5v or 0v on your esc.
   You don't need to cut away heatshrink for that. It's doubly worth your time because it is when humans enter the production process of printed circuits that errors occur. A specialist fabricator company will probably ship large dies containing many milled and prong tested boards. These boards likely get separated, soldered and packaged at a human sweatshop that specialises in that.

[Umi_Ryuzuki]

I didn't post this earlier, as you specified "Cheap" esc.
Dimension Engineering makes several dual (2x) ESCs/mixers.
https://www.dimensionengineering.com/products/sabertooth2x12rc

[HMS Invisible]

 Some more info on dodgy geezer's dual esc and a correction to my earlier post (link) with confirmation/explanation in the pdf datasheet why a two amp current rating is more realistic.
The correction is that it does have mix option and that's what the mystery sw1 is for.

For people interested in aspects of printed circuit and electronic circuit design the 5a dual esc uses a monolithic integrated circuit and not multiples of four discrete fets of the bigger escs for motor drive.
If you are one of those who outright moaned about technical stuff in my posts you are going to hate the rest of this post. A fair bit of what I trot out is not addressed to you. It's for the IT specialists, technicians and Arduino & PIC hobbyist members of Mayhem. Enough technically competent people have bent my ear to diy their own escs and gadgets to make that traffic answered best in one version in one place. If you are one of those then take a look at the pdf and experiment with equivant chips. With 2.4G sets you no longer need 2kB of machine code to simulate a clean signal from a weak 27 am/fm link and all the rf glitches. You still need it for noise from inadvisable boat wiring practices like shared batteries. Keep component count low but to stay bulletproof use similar monolithic ICs for motor drive and add the cake decoration of warning lights and chirps last of all.

In Chinglish the datasheet (pdf download link)) says of Contnuous Current

Around of the no.5.6,7,8 pins needs copper to auxiliary heat dissipation

and  Page 2 is an illustration of why you derate a power semiconductor on a small area circuit board. It's the unetched area of copper plane connected to the component's hot drain or Vcc pins that sets the real world power dissipation figure and amp rating before the 130C limit & shutdown.

The pdf on the UIRZ886 gives extensive information on the motor drive fets. I evaluated samples of these chips when they came out. They equate to four 0.06 ohm fets with full bridge drive and protection circuitry. So it's a neat little device. Unfortunately for me around 2010, they were not about to come in the high power packages and current drive rating to enable me to manufacture 20+ amp capable rc escs in the ten components of this product.
The other great aspect of the one-chip motor bridge is the 130C sensor is a pn junction integrated in the silicon die so gives effective overcurrent protection and won't be cooked by the 7805 bec if it delivers 400mA at 3s input to pre- heat the board with (12.6-5)× 0.4 watts.
The dual esc in the photo.
 So for a basic 2s, 2 amp esc this would be a good choice if it is fully proportional with no fwd to reverse delay.
All the little Chinese single 10,20,30 amp escs I sampled started at 15% duty which is not proportional and no good for the smallest of dodgy geezer's models. It lacks audible and visual diagnostic feedback because the monolithic chips and not the processor does the protection and monitoring task. A 2s voltage bargraph or voltage monitor would help. I am not going to bench test for effective lipo protection. It's 2024 so omit that and keep to a minimum component design. Just buy a 2s or 3s bms from Ebay and piggyback it on to your battery and protect everything if you can get it in a bms module.
I know the component layout of this pcboard with "payne" silkscreened on the underside differs from dodgy geezers version.

[HMS Invisible]

Let's see if the photo uploads.....

[Circlip]

Well, you did ask, Dodgy. 


 Regards  Ian.

[HMS Invisible]

Dodgy, the inference for you from from UIRZ886 datasheet information and my prior photos is that there is good chance a working 5 amp dual might just be the ticket for your small 1s application by bypassing the 7805
 It remains to be seen whether it is or not.
 The only forensic tests I see you can do without snipping heatshrink is the continuity test from inputs to 5v and 0v to pick up a soldering short.

[dodgy geezer]

Got a refund and stripped the heatshrink anyway to have a closer look at the components. There's an led on the board which I can get to light intermittently by plugging in the battery and motor - but when I plug in the Rx connection everything goes dead.. .

[HMS Invisible]

Without a better photo to sketch a circuit, the led flicker is > 90% chance of a processor fault if it is driven from it and it has a good supply. That's why, to be sure, you have to measure Vcc of the processor & eliminate it being an undervoltage condition. That's where a 2s input lessens the chance over a substandard  6v driving a servo load.
Very encouraging update for 1s application
I tested my working 5 amp "dual" at 2s with pair of high rpm 360 motors.
On battery connection the esc beeps both motors with a rising then a falling tone with one or both channels hooked to receiver.
A single rising tone is made if no connection to receiver.
 There is no led on mine.

Onto performance at 1 s level
Still with the 7805 bec and its aforementioned poor voltage drop,  the servo tester bursts into life at 4.0 volts with the 7805 bec dropping a whopping 1.3 volt for 2.7 volt at the logic and servo tester.
It's getting late so I'll wait until the morning to run more sedate prewired 555 motors from a single 18650 cell. I'll bypass the 7805 with a short from the in to out pin and test the minimum throttle for reversing delay, for proportionality or if its minimum  is 15%, which you don't want.

[HMS Invisible]

I soldered a link across the bec from in to out pins and nothing more.
My "payne" marked board version is working down to 2.80 volt with high turn 260 motors.
Operation from a psu below 2.75 volt triggers the esc processor to stop the motors and give the beep code for power-on.
I'm not testing for minimum throttle duty percentage as I'm hearing a 2kHz whine & seeing tick over speed.
You couldn't wish for better test results save the price. The rest is down to the quality of the battery cell and length of the leads.
I took relevant photos but 400k isn't uploading this morning.