broadcast mode for spinning beginners....

Anubisbot

Hi, since i got the prop i have fun playing with it.
Now i try to find out to send the the tV signal over broadcast so i dont have to unplug the propboard and run to my tv every time to look at changes.

What do i have to change to do that.

I have read that you have to change the mode to 0100 but where, and 55_000_000 or 55_250_000 and where to change that

i have the first 4 pins p0..p3 for the tv hocked up.

How do i do it ?

Anubis Bot

Anubisbot

Update, after i messed around with it i only get black and white picture but not over VRF... Help!!

CJ

check this out http://forums.parallax.com/showthread.php?p=600706

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Dennis Ferron

Hey I wonder if you could use an amplified TV antenna with this. Just buy an amplified antenna, and reverse the orientation of the amplifier circuit. Reroute what was the antenna input to the prop, and send the amplified output to the antenna. Would that work?

Anubisbot

ok i went and did all discribed in the post, but i have to hold the prop bord about 10cm from the tv to use the auto scan on the tv to find a channel.
And i only get a black picture with some blue and green flickery on the tv.

Do i nned some extra hardware like a antenna ?

Anubisbot

Anubisbot

Hi, ok i made some more reserch, and can it be that i dont get a lock on to the channel ,
because i got a 5 mhz crystal, but in the Crystals PDF it says only good for 3,567 to 70 MHz

Does this means that i only get my prop running at 70 MHZ and would that kill my tv Broadcasting.
Funny part is that when i hoock it up to the tv in baseband it works fine.


Anubisbot

CJ

add a little bit of wire to the output for an antenna, and try 60,000,000 for a clean broadcast frequency

5mhz is the recommended frequency for the crystal, used with 16xpll it gives you 80Mhz

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CJ

let's not forget that the TV needs to have an antenna too, kinda hard to pick up off the air without one

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Mike Green

If you're using a 5MHz crystal (or a 10MHz crystal on a Hydra), you may notice that the broadcast signal is not great quality, particularly in color. This is because of "jitter" in the broadcast signal due to the fact that VHF broadcast channels are at multiples of 6MHz in frequency. If you substitute a 6MHz crystal (and get a 96MHz system clock), you'll get a less "static-y" signal on the low VHF channels (#2:54-60MHz, #3:60-66MHz, #4:66-72MHz, #5:72-78MHz).

If you use BW-only, you'll also get a cleaner display.