Mr.RC-Cam

HeadPlay HD Goggle Upgrade: Add 5.8GHz Diversity & DVR

36 posts in this topic

Again, I understand that I have an off brand Chinese diversity module, and you may not have answers for me.  I have my China Diversity module connected without your buffer at the moment.  It wold turn on then shut down to just a series of Chinese letters.  Well I switched from my 3 cell to a two cell and now it works fine.  On the three cell is shuts back down. The voltage going to the diversity module is 4.2v on the two cell (maybe needs a charge) and 4.85 on the three cell.  The module says it wants 3.5v to 5.5v.  At any rate, I bought the low voltage 5v buzzer as well and the module has the circle where it goes, but what is the point of a 5v low voltage buzzer on a device that is regulated to less than 5v anyway?  I am a bit lost.  My brain says perhaps I have a module that wants about 4.5v an I need a variable voltage regulator but not sure what the point of the buzzer will be in that case. 

Edited by Kingdon Humann

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The first time I powered mine the OLED showed English text and the menu nav switch worked.

Edit: There is something wrong with your board if it does not accept 5.0V. But regardless, the typical "5V" Mag buzzer will work on less than 5V, some buzzers will continue to work as low as 3V with a slight reduction in volume. Furthermore, the buzzer is optional, so don't worry if you decide to not install it.

 

Edited by Mr.RC-Cam

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Thanks.  It gives me a data point though Im not sure what to make of it.

Edited by Kingdon Humann

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Thanks again.  Sounds good, though I agree something seems amiss.  Time to sleep.

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Sounds good, though I agree something seems amiss.

The thing about the Chinese FPV board cloners is that they rarely know what they are doing. On top of that, the eBay sellers are clueless too. It's double jeopardy on our end due to poorly designed copies and error prone published specs.

I looked at the photos shown in your eBay link. Assuming that you received what is shown there, I highly doubt their claim that it was designed to run on 3.5-5.5V. Evidence suggest that it has a onboard 5V VReg that expects 2S-3S. See my comments in the images taken from the eBay ad:

dc-pwr1.jpgVreg-5V.jpg

There's also a design error on the VReg. The VReg IC's input leg has a 1K resistor on it that appears to connect the 2S-3S power input to ground (not sure why they did that). There should be a small value cap (0.1uF is typical) directly on the VReg's power-in leg to ground to ensure VReg stability.

FWIW, because they used a linear VReg be mindful of excessive heat / thermal shutdown if you power it with a 3S. If it gets blazing hot on 3S you might be better off with using 2S instead.

 

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wow!  Thanks so for all the info.  You totally went out of your way.  I found that on the edge of our Headplay board there is a 12v a 5v and a 3.3v solder pad.  I connected the Chinese diversity up to the 5v and a ground and took my own voltage regulator out of the circuit.   It seems to work fine now, on my bench at least.  Goes through all its menus and displays which receiver A or B is getting the best channel.  It does seem to have trouble finding my channel.  Often stops on some random channel or right near my channel..  At least it reads it out and allows me to adjust manually.  I like this thing. I can run my clover leaf and my helical antenna at same time.  Raining some more for the next few days but for now it seems functional.  I will try to hunt down the voltage reg on the Headplay board so I can make sure that isn't heating up.  All in all a great idea by you.  Thanks for your trouble shooting ideas.  I think my problem was putting my v regulator on the 12v solder pad next to the video pad.  The cheap reg I have heated up the Headplay board until it finally melted a trace this morning on 3s.  Fortunately I was able to repair it and all is working well now.  

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I found that on the edge of our Headplay board there is a 12v a 5v and a 3.3v solder pad.  I connected the Chinese diversity up to the 5v and a ground and took my own voltage regulator out of the circuit.

Just my opinion, but I'd recommend using the built-in VReg or another dedicated VReg to power your extra stuff. This will reduce the burden on the Headplay VRegs.

EDIT: BTW, if you are connecting external power to the 2S-3S input then keep in mind that applied voltage needs to be at least 6V for the internal 5V VReg to work correctly.

 

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It does seem to have trouble finding my channel.  Often stops on some random channel or right near my channel..  At least it reads it out and allows me to adjust manually.

This is not unusual; The Autoscan feature on many FPV receivers is subject to this issue. Convenient in principal, when autoscan is used it can be fooled by your nearby 5.8GHz vTx's strong RF signal and cause an adjacent Rx channel frequency to be chosen instead of the exact match. The big surprise occurs later -- The video image will look fine until your model is 25-100 meters away. Then the mismatched channels will drop the video link like a rock and you'll be flying blind. Avoid this by setting it manually to the correct frequency that matches the vTx.

 

Edited by Mr.RC-Cam

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Signed up just to say THANK YOU for all the work you put into both the project and the writeup.  Bookmarked for future project!

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If I (electronically muddled) can get this to work, so can anyone else who is willing to ask a few questions along the way.  I now have my clover leaf antenna and a helical antenna working simultaneously, plus I can see what channel I am set to on the readout.  This rocks!!!

Edited by Kingdon Humann

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Thanks for the feedback!

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