RF602 TX is klling my gripped XTi's batteries.

I received my RF 602 transmitter with two receivers today and overall, I'm impressed. No shots missed, good range etc etc.

But after shooting around 40-50 shots, my gripped XTi (with two fully charged batteries) ran out of juice. Now I wasn't using on camera flash, just the RF602 on the hot shoe, triggering one Yongnuo receiver.

Generally these batteries last me a long long time (don't know the exact number, but ballpark estimate say 700-1000 shots). To check whether something was wrong with my batteries, I replaced these with another completely charged pair and after about 40-45 shots the same thing's happening.

Can someone please tell me what I can do? I bought this from the legit dealer "hkyongnuoequipment" on eBay. They work fine, it just seems like the transmitter is shorting the hot shoe or something and sucking the batteries dry.

Any thoughts?

wow thats weird. I have an Xti and have used my 602's to trigger my YN-468 a few times. I haven't experienced this battery loss. I use the grip also. I'm not very familiar with hot shoes, but would the transmitter be passive and the camera would have to decide when to send it power (such as sending the fire command) or could the transmitter draw power on its on (but why? it has the battery).

From simple electronics, the transmitter should only receive a signal from the camera and then by using it's own battery, the transmitter should send the signal to the receiver.

Something is very very wrong right now.

powerslave wrote in post #10568404
From simple electronics, the transmitter should only receive a signal from the camera and then by using it's own battery, the transmitter should send the signal to the receiver.

Something is very very wrong right now.

Ok, so my understanding was correct. I know that if a flash is mounted then some signal will be transmitted back into the camera body, but as far as I know, these transmitted only receive signals and do not send.

Hopefully someone can offer some insight. Mine definitely doesn't have this problem, and I never saw it come up in the RF-602 thread.

Try shooting without the grip. Most likely it could be the grip and not the transmitter.

Jardiniboy wrote in post #10569415
Try shooting without the grip. Most likely it could be the grip and not the transmitter.

I tested it without the transmitter and it seems to hold the charge well. So I know it's the transmitter.

I think it's going back to HongKong for a refund for what it's worth.

What kind of batteries are you using on your XTi? Are they third party? Which brand? What are the power ratings on them?

Well they're the sterlingtek ones (NB2LH rated at 1200mAh). I have no reason to believe both sets will start malfunctioning at the same time, especially since I've been using them without any problems whatsoever for two years now. And not just that, they work fine without the hot shoe mounted trigger.

Does the hotshoe... get... "hot"? No really, does it? Is there shorting of some kind? Can you take a picture of your RF-602 transmitter's foot? Did you get a Canon version or a Nikon version?

BTW, I'm not saying the RF-602 isn't defective. I'm just trying to help you out get to the bottom of this before you send it back for a new one or for a refund.

I know I know, eliminating all possibilities to make sure the problem is indeed with the TX.

Yeah, I did check for the hot shoe being hot, but it was just an afterthought, I think it warrants another attempt. I'll try that and see what it does.

I did get the transmitters for 400D specifically but as I understand, hot shoes are standard and the specific connections matter when using smart modes (Ettl etc) only and not manual mode. So I guess it shouldn't be an issue. Feel free to correct me though.

The TX/RX set is for the 400D specifically anyway so this shouldn't be a concern here.

Actually, the RF-602s don't have TTL functionality but their foot has pins for it. This is the reason why I asked if the one you currently have is for Nikon or Canon.

powerslave, I just confirmed with my best friend who has a Canon XTi with Canon battery grip that his also runs out of battery very fast, has some misfire issues, etc. He has the Nikon version. The pins on the feet seems to be causing some short leading to malfunction. In my experiments with RF-602s, the Canon version seems to work fine with Nikon but not vice versa.

Please verify the RF-602 transmitter you have. The receiver on the other hand is universal.

Alright, I'll post up a picture of the foot of the transmitter I have (at lunch time EST ) and hopefully someone already has pictures of the Canon versions' foot on here. Let's see what we find.

Thanks a lot for the help seanzky!

No problem. I thought your problem sounded very familiar to my best friend's.

If you can upload the picture, I'll know if it's Canon or Nikon.