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dominguez, 7.2.2009, 19:58, 88.17.167.232
Finally I have the stereo coder working fine. The only problem I had was programming the PIC since I only got errors until I modded the programmer. Well, I have a question: the input op-amps are biased to +2,5V, but their supply is 12v. This would cause the multiplexer chips 74hc4053 to receive at their inputs signals greater than +5v, which is their limit. Have you noticed this fact?
And an observation: The coder might work better using a symmetrical +-5V power supply, utilizing the -vee pins on the 74hc4053, this also can save electrolytic capacitors in the singal path and use better op-amps, such as opa2604.
Thank you very much.
Jan, 12.2.2009, 10:06
You are true in all points. But this is not a problem if input voltage does not exceed 5 V pp as specified. All other parameters are not affected. This is ok for almost all applications. Symetrical power supply may save some parts but the power supply alone requires more parts and in some cases it's very hard to realize (portable applications - clear spectrum converter required).
Abo, 31.3.2009, 16:42, 84.0.183.138
Gerber File - Reply
Hi Jan,
Could you send me please the gerber file of the coder? The picture resolution is to low.
Thanks,
Abo
abo@huligan.hu
Jan, 31.3.2009, 21:18
Re: Gerber File - Reply
These files are not available since the design files were corrupted and the final operations were made using bitmap editor. It's needed to redraw the board first.
Abo, 1.4.2009, 12:59, 84.0.181.97
Gerber File - Reply
Hi Jan,
Thanks for the quick reply.
I am going to redraw it in Altium.
Abo
djrenzo, 7.4.2009, 13:32, 194.57.192.118
stereo coder and erds v1.1 - Reply
hello is there possibility of sycrhonizer the 19 kHz stereo encoder pira for ERDS v1.1 ? pira merci for excellent stereo encoder
djrenzo france bretagne !
blast84, 7.7.2009, 10:44, 86.35.248.83
i think i have a problem with this stereo coder.when i press sw1 and hold it nothing happens,i mean it doesn't change the mode.i hear o sound but not a beep or many
TED , 10.7.2009, 03:24
no mpx input ... - Reply
hello !!! i have an old professional mono fm exiter and i would like to upgrade it to stereo using your stereo coder...unfortunately the transmitter haven't got any mpx input but only one audio input...anyone got an idea how to modify my pll circuit in order to connect the stereo coders mpx signal ;;;
MAMBAS, 10.7.2009, 13:18, 196.46.2.178
Re: no mpx input ... - Reply
Hi Ted,
Just try to use your available audio input. If there is no preemphasis circuit, the only thing you may have to do, is adjusting the input sensitivity. If there is a preemphasis circuit you have to disable it. Good luck. Let us know your results. Mambas
TED , 10.7.2009, 15:29
Re: Re: no mpx input ... - Reply
Thanks MAMBAS i'll inform you with my results as soon as i can !!! The pll circuit board is an old cdm electronics pll that drives the amplifier unit with 1 watt power output using 2n4427 transistor it uses push weels to change the frequencies... i provide you this information in case you know about this pll
blast84, 13.7.2009, 22:26, 86.35.248.83
i think i have a problem with this stereo coder.when i press sw1 and hold it nothing happens,i mean it doesn't change the mode.i hear a sound but not a beep like you said!please answer
henry, 2.11.2009, 15:00, 84.88.233.91
stereo coder - Reply
hi jan! i have build stereo coder and works amazing. i have connected it to my pira compressor that i have made before. i will send you pictures later of compressor and stereo coder.thanks for the knowledge, more power
TED , 3.11.2009, 22:43, 94.71.199.227
Re: Re: no mpx input ... - Reply
Finaly i tested the stereo coder i've build directry through the mono audio input. I adjusted the trimmers correctly and the audio input of the exiter...The results are awesome !!! Crystal clear stereo sound quality !!! Like Henry i would like to thank you for sharing this knowledge !!!
MAMBAS, 4.11.2009, 10:29
Re: Re: Re: no mpx input ... - Reply
You are welcome. Funny enough, yesterday I was wondering what was happening to you. That was an easy question to solve.
Whenever I can, I answer to some questions so that Jan can deal with more complex questions and have time for research... Congratulations. MAMBAS
TED , 9.11.2009, 23:09, 94.71.173.181
Re: Re: Re: Re: no mpx input ... - Reply
I believe that you deserve the congratulations !!! it took me so long because i build also the pira cz 7 watt transmitter and the results were amazing also for this unit !!! both pira cz transmitter and pira cz stereo coder were tested from the research laboratory of the technological institute of athens whith a full fourier analysis signal and spectrum analyser. I am studing to this university and they gave me the oportunity to test them in this lab so when i talk about awesome results i mean it !!! THANKS A LOT MAMBAS AND JAN AND OTHER MEMBERS OF PIRA CZ !!!
MAMBAS, 10.11.2009, 06:33, 193.37.153.13
Re: Re: Re: Re: Re: no mpx input ... - Reply
Don't mention it. It is good to hear from you.
Lexx, 24.1.2010, 09:10, 95.68.206.231
18f1220 - Reply
Good afternoon, friends, for me large problems with programirovaniem PIC of inspector 18F1220. I utillize programator J D M together with Ic-prog. I utillized other software similarly - but a result was not. pozhaluyta prompt me what programatorom you use . . .
I already collected your transmitter on 5 watts, and ostal'sya is high pleased!!! please help me with a stereo koder.
Bob, 17.2.2010, 15:31
Reg Stereo Encoder - Reply
Jan,
I am planning to build this circuit.
1) I dont have this Resistor Network.Can we use normal 1K resistors in its place?
2) What should be the ideal source of Audio input for this circuit?Can an MP3 Player used as the source?
henry, 7.4.2010, 15:28, 84.88.233.143
Re: 18f1220 - Reply
Hi Lexx! I have progammed many times pic18f1220 for my stereo encoder using the IC-prog with microJDM and it works very well. You can surf for the internet for microJDM schematics to programes your pic. let me know the results. good luck
Joperator, 28.7.2010, 12:12, 41.190.90.50
How do I program PIC18F1220 - Reply
Pls I have got all the necessary parts for the st.encoder but it's left with programming the PIC.
pls advice me on what to do,the software to use and the hardware to use,and how to program it.Finally, the code for the program.
Thanks
E-mail:joperators@yahoo.co.uk
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