DX7 Voltage Reading?

[KG4HFV]

Did a quick search and didn't come up with anything...When I change models why does my voltage reading differ so much. Right now it shows 10.3v on one model and when I change models it will show 9.8v. It shows various readings for varoius models but not usually more than 1/2 volt...

[KG4HFV]

Im guessing nobody else has this problem.....

[Madani]

If the voltage reading drops compared to the time you turned the controller on, and around half a volt, it could be normal. It might indicate the battery aging or not holding enough charge.

[Badevakt1]

If the DX7 is bound to a DSM receiver (e.g AR6000) it will use much more power (more than twice) than if it's bound to a DSM2 receiver (e.g AR7000).

[kamtsa]

If the DX7 is bound to a DSM receiver (e.g AR6000) it will use much more power (more than twice) than if it's bound to a DSM2 receiver (e.g AR7000).

I wonder, how does the DX7 know what receiver it is bound to? Is there a setting on the DX7 for the receiver type?

Kam

[Badevakt1]

No, there is no setting for the receiver type, I believe it determines which while binding.

[kamtsa]

No, there is no setting for the receiver type, I believe it determines which while binding.

I don't think it can since the RX does not transmit any information back to the TX.

[Badevakt1]

OK, I don't know for sure, but here's a guy who have tested the amp draw with/without a linear regulator in the DX7.

http://www.rcgroups.com/forums/showpost.php?p=6523231&postcount=659

[kamtsa]

OK, I don't know for sure, but here's a guy who have tested the amp draw with/without a linear regulator in the DX7.

http://www.rcgroups.com/forums/showpost.php?p=6523231&postcount=659

The guy says clearly that in his experiment, the choice of receiver affected significantly the current draw of the DX7.

Anybody has any speculation how RX choice of receiver affects the TX current draw?

It does not make any sense to me since the TX does not 'know' what RX is used. I would even speculate that a TX can be bound to multiple RX's at the same time for the same model since the binding is done in an open loop.

[TheSteve]

DSM receivers don't transmit however DSM2 receivers do transmit a packet during binding giving information such as resolution.

[mmarian]

I know that this is slightly off the topic but I've noticed the same thing when switching from sim to real heli. Is the TX actually transmitting the radio signal when the sim plug is inserted? I thought that the plug disengages the transmitter section of the TX, thus drawing less power and that is what makes the voltage reading higher. Maybe I am wrong in my assumption, though.

[kamtsa]

I know that this is slightly off the topic but I've noticed the same thing when switching from sim to real heli. Is the TX actually transmitting the radio signal when the sim plug is inserted? I thought that the plug disengages the transmitter section of the TX, thus drawing less power and that is what makes the voltage reading higher. Maybe I am wrong in my assumption, though.

Yes, plugging the sim connector disables the transmitter and should draw less power. It also stops the speaker buzz (in case your DX7 has this problem).

[kamtsa]

DSM receivers don't transmit however DSM2 receivers do transmit a packet during binding giving information such as resolution.

Good to know. Thanks.

[Pinecone]

And that is why if you accidently push the bind button when turning on your Tx, you will "unbind" a DSM2 Rx. What really happens is when you power up the Tx with the bind button pushed, the Tx listens for the Rx on one of the channels (there are 40 Spektrum channels, but only 39 are usable, the 40th is reserved for this). and if the Rx is DSM2, it "hears" that signal and goes to DSM2 mode. If it doesn't hear anything, it switche to DSM mode.

The Rx only transmits in bind mode, so if the Tx is in bind mode, while the Rx is not, the Tx doesn't hear the DSM2 signal so switches to DSM, so the Rx can no longer"hear" the Tx.

[kamtsa]

What really happens is when you power up the Tx with the bind button pushed, the Tx listens for the Rx on one of the channels ...

Interesting. Its definitely makes the binding easier (as opposed to setting the RX type manually).

Kam