Sunip 35Mhz rceiver

[Chippie]

I have two of these from Ebay and both seem dead....

With a crystal inserted and powered from a 4 cell pack, there's no response from a servo plugged in to any channel..

As the ics have had their id numbers obliterated, there's no telling what they are...

Does anyone have any experience of these receivers and any idea on repairs?

[KraftyOne]

I have a couple on 40Mhz, crude little hand-soldered jobies, :eek: but they work OK in my park foamies & slope machines.

Provided your wiring is OK, correct polarity, etc., I would suspect xtals are not correct. I'm using a couple that were cut for Micron receivers, some others I had would not work.

[Chippie]

xtals are brand new and work ok in other rxs

[kevingill]

I've bought 4 of these type of Rx - all work fine.
But I did note that they were finicky about the crystal I put in.
In the end, I bought a set of Tx/Rx ESky crystals and they work great with a Futaba Tx.

Can you send them back to the EBay seller?

[KraftyOne]

I am using a Multiplex trany, but Multiplex 40Mhz receiver xtals would not work in the receivers, which is why I used the Micron ones.

EGB.

[Chippie]

A new receiver arrived today...

Had a look at the internals and it appears to be slightly different to my 2 originals....( er.. this one works by the way...)

I'm thinking along the lines of Positive or Negative shift....as the reason why my 2 older ones dont work with my Futaba tx....

Anyone got any thoughts on this?

Can they be modified? if so how?

[heli_ebook]

Are you guys referring to the "SunUpp (http://cgi.ebay.com/Sunupp-Model-SU-R-6FM-PPM-6ch-FM-72MHz-Micro-Receiver_W0QQitemZ300271473437QQcmdZViewItemQQptZR adio_Control_Parts_Accessories?hash=item3002714734 37&_trksid=p3286.c0.m14&_trkparms=72%3A1418%7C66%3A2%7C65%3A12%7C39%3A1%7C 240%3A1318) " eBay listings? I was curious about them too and if their noise/glitch filtering is appropriate for BL equipment? Here's the other one (http://cgi.ebay.com/RC-EP-plane-FM-mini-receiver-72mhz-PPM-6-channel-New-7g_W0QQitemZ110307777974QQcmdZViewItemQQptZRadio_C ontrol_Parts_Accessories?hash=item110307777974&_trksid=p3286.c0.m14&_trkparms=72%3A1418%7C66%3A2%7C65%3A12%7C39%3A1%7C 240%3A1318).

[Chippie]

The other one you refer to is the one I bought but the 35mhz version..

[heli_ebook]

The "SunUpp" seller responded to me today regarding noise filtering and glitch issues.
"This has none of those features" he replied. It's not a feature. As usual, ebay sellers know not what they are selling!

[heli_ebook]

Here's a QUICK and EASY way to weed out a BAD receiver: Turn Tx on, then the Rx. Touch your hand to the COLLAPSED Tx antenna. Or touch the Tx antenna end to your car's radio antenna.


Did the servos JUMP??? Yes? JUNK IT, IMMEDIATELY! This simple test is a true giveaway to tell you there's NO noise filtering circuitry.

Touch it... servo jumps... Junk it!

[Bruce Abbott]

The "SunUpp" seller responded to me today regarding noise filtering and glitch issues.
"This has none of those features" he replied. It's not a feature. As usual, ebay sellers know not what they are selling!Nowhere in the advert does it say that they do have 'noise filtering' or 'glitch filtering'. The mini receiver has a 'Mircoprocessor decorder', whatever that is :rolleyes: . OK, I think they mean that it has a microcontroller in place of the conventional decoder chip, but that doesn't mean that it filters noise or glitches (same goes for the Hitec HFS-05MS/Micro-05).

The other thing of note is that it only has one tunable coil. This suggests that the rf input is wideband, like some other ultra-miniature receivers eg. GWS R4P. This probably puts it into the category of 'short range park flyer receivers that glitch a lot', but what do you expect for $0.10?

[Chippie]

The decoder 'switches all the outputs off' when the tx is switched off....resulting in the servo's not moving in the usual way...

I've resolved my issue ;)

I moved two resistors around what looks like the comparator chip...I'll post up further details along with pictures...

My thanks to Bruce Abbott for the GWS circuit that aided me..

[rowlsearle]

I've got a couple of these RXs, and use them in anything from a foamy up to a 60size trainer (wouldn't trust them on aything bigger), and all of them have worked flawlessly. All on 35mhz, I use a JR TX, and have used JR & Esky crystals. I've only got good things to say about these simple cheap receivers - my 2c worth.