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Posted: Tue May 15, 2012 4:44 pm
by jackssmirkingrevenge
I'll make a test one and we'll see how that goes

but I will try and make the battery removable for the first one at least.
Posted: Tue May 15, 2012 5:35 pm
by al-xg
Ah, but this one only beeps when you tell it to
Am I missing something here ? I'm with Poland_Spud on this, if the sound is going to be coming from the projectile what is the point of the RF ?
Posted: Tue May 15, 2012 5:41 pm
by dewey-1
JSR;
Have you considered a CR123A battery rather than the 2 NiCads?
The CR123A is even better than the CR2032 for battery life.
They even make a RCR123A that is rechargeable.
http://www.batteryjunction.com/uf16340.html
Send me closeup overhead pictures of both side of the recetver without the battery installed.
I can then read the parts used on it. Better with no flash.
Did you take pictures of the transmitter? If possible do the same thing with the images.
Posted: Tue May 15, 2012 11:48 pm
by jackssmirkingrevenge
al-xg wrote:Am I missing something here ? I'm with Poland_Spud on this, if the sound is going to be coming from the projectile what is the point of the RF ?
I understand the "what's the point of RF when you can just have a 'permanent' beeper on the projectile" objection, but this is a sort of budget way of seeing how the electronics hold up to the stress of being fired and hitting the ground.
The 'lectrics were
dirt cheap and for that price I get to make 4 units to play with without risking a pricier RF unit.
Have you considered a CR123A battery rather than the 2 NiCads?
The CR123A is even better than the CR2032 for battery life.
For these I'm going to stick with the standard battery (CR1632). For the RF transmitter, AAA or AA cells should suffice, after all compactness is not an issue in an elongated tube and they will add mass and sectional density.
Send me closeup overhead pictures of both side of the recetver without the battery installed.
I can then read the parts used on it. Better with no flash.
Did you take pictures of the transmitter? If possible do the same thing with the images.
Will do this evening. I'm sure an antenna can be hooked up to the transmitter as well and improve the range even more.
What do you think of my idea to have wire wrapped around the "outline" of the fins as an antenna?
Posted: Wed May 16, 2012 1:22 pm
by jackssmirkingrevenge
Some close up pictures of the transmitter and receiver. The bit of wire around the receiver board is something I added as an antenna. I tried bending it in various configurations, unsurprisingly having it straight worked best. Range increased about three times that in standard configuration.
Posted: Wed May 16, 2012 2:00 pm
by dewey-1
A straight antenna is typically the best choice.
Adding a straight wire for the transmitter will also help.
The lengths of each should be equal. I could probably tell you optimal length if I knew the RF frequency.
Was there a manual/spec sheet with it?
I thought maybe the pictures would show the part numbers on the ICs.
I can tell that it uses 13.225600 MHz crystal.
It probably is 433.92 MHz therefore a 170mm antenna could be used.
Posted: Wed May 16, 2012 2:38 pm
by jackssmirkingrevenge
dewey-1 wrote:Was there a manual/spec sheet with it?
nope, in typical eBay product style it was all bundled in an envelope with no packaging
I thought maybe the pictures would show the part numbers on the ICs.
Only one of the ICs has visible markings
I can tell that it uses 13.225600 MHz crystal.
It probably is 433.92 MHz therefore a 170mm antenna could be used.
Good to know
Any objections to encasing the whole thing in epoxy, battery and all? Except the switch of course

Posted: Wed May 16, 2012 3:04 pm
by dewey-1
Go for it!
What launcher/barrel ID is this for?
What is the number on the IC? U1 or U3 of the receiver?
It appears to be a FM FSK receiver and transmitter.
freq= 13.2256MHz x 32 + 10.7MHz= 433.9192MHz or 433.92MHz.
Posted: Wed May 16, 2012 10:07 pm
by jackssmirkingrevenge
dewey-1 wrote:Go for it!
What launcher/barrel ID is this for?
Petitlu's beast, fitted with a 33mm barrel
What is the number on the IC? U1 or U3 of the receiver?
It appears to be a FM FSK receiver and transmitter.
freq= 13.2256MHz x 32 + 10.7MHz= 433.9192MHz or 433.92MHz.
It's U1
PT 4302-X
T8I3 1C (maybe)
APCS37
Posted: Wed May 16, 2012 11:28 pm
by dewey-1
Here is data sheet for PT4302-x receiver IC.
The transmitter is probably the PT4450.
http://www.princeton.com.tw/
Posted: Wed May 16, 2012 11:33 pm
by jackssmirkingrevenge
Literally all Chinese to me

Posted: Wed May 16, 2012 11:38 pm
by dewey-1
jackssmirkingrevenge wrote:Literally all Chinese to me

It still is even if you use English!
It still gives you some information you can understand.
Posted: Thu May 17, 2012 5:09 am
by Petitlu
good, the missile is progressing well
Now I will start making the launcher!

Posted: Thu May 17, 2012 1:48 pm
by Petitlu
hybrid :
-800cl chamber

Posted: Thu May 17, 2012 2:46 pm
by jackssmirkingrevenge
Damn that was quick!
I need to catch up
That looks perfect, it can function as a burst disk pneumatic and a low pressure hybrid!