Radio Data System (RDS) > PIRA32 RDS Encoder

I want to do testing of RDS on a reciever

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mitchjs:
i want to test RDS for a receiver design, while over the air rds works from local stations, i want to do the RDS and mostly RT+
tests

with this encoder can you recomend a cheap fm transmitter, that i can maybe mod, to inject the RDS Data
i only need like 5 feet worth of transmittion, i know you say steer clear of BH1415s, how about BH1414ks?
is there some cheap fm transmitter like for ipods that i could mod... they prob all use bh1414s

thanks
mitch

Jan:
Devices built around BH141x do not accept RDS signal. Based on theory of operation there's a modification possible but we have never tried it. Since the FM modulator is outside the IC, there's probably a possibility to disconnect MPX and pilot from it and feed an external RDS signal into it, like on this picture:



In practice it may be hard to locate the parts necessary without more information from the device manufacturer.

For simple testings it may be easier to build some 1-transistor FM bug, keeping it in constant temperature and position its frequency is stable enough.

mitchjs:
ok, looking at that, i see injecting the rds signal, but doesnt the PIRA32 need the 19khz pilot signal from the fm stereo encoder?
or will this be "good" enough...
i saw people in a forum, tapping into a belkin tunecast II, like this...
they clamed it worked, using your old minirds, which i cant use cause it doesnt do RT+ (right?)
or your microRDS?


thanks
mitch

Jan:
In fact, the quality of the BH141x chips is so low to allow the pilot synchronization to be omitted without any negative effect notable.
MiniRDS/MicroRDS can transmit RT+ only by means of the raw groups, ie. you must write a special control software for this purpose which will translate RT+ content into RDS groups and send to the port. The PIRA32 supports RT+ directly.

mitchjs:
ok, thats a possibilty...

the RT+TAGS, go in what ODA Group, so that receivers recognize them

11A?

so.. i would set up PI, RT, and then a UDG1 as 11A with RT+ item, position, len
packing that all into BBBB CCCC DDDD

thanks
mitch

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