RDS Decoder

[rdees]

I've been toying with the idea of producing a replacement for the Conrad RDS Manager. A few of my ideas are:

Four line LCD display with adjustable brightness/contrast.
Adjustable input sensitivity (FM multiplex).
Powered via wall wort or USB port.
9 pin D supports Esslinger's RDS decoder.
USB serial data - Could output vaild RDS blocks for those who want to write their own software or decoded RDS data.
Decodes US/Canadian call signs (If they send out the correct PI code).
Displays North American Program Type codes (PTY).
Displays Radio Text A/B all at one time - not scrolling.
Has three basic modes - see pictures below.

I have a few questions:

Is it acceptable to discuss this project in this forum? If not then please delete this message! How much interest is out there? Is there a consensus on the format for the data that is sent via USB? Any comments would be appreciated!

Thanks for your help!

Ray

[K4NBF]

Ray,

This is absolutely appropriate, based on previous discussion here.

This project looks great to me. I would certainly purchase one if you were to put them on sale. I have an extra T-9090 tuner with multipath jacks that I'd like to use, and this would be perfect for that. USB seems to be the easiest format, and everyone has it.

Brian/K6STI posted a thread (http://www.wtfda.info/showthread.php?t=3170) several months ago with an idea for a more sensitive RDS decoder, you may want to talk to him about this.

[Mike-CT]

Perfectly acceptable! Go for it!
I like your screenshots. PS plus PI codes on one screen. If only the RDS Manager did both at the same time. I'd buy one.

[Russ-PA]

I have two Conrads, one modified by Bill Nollman, the other stock. Having the screen show calls, & PI at once is great. It'd also be great to get something comparable to the sensitivity enhancement Bill did on the Conrads as a built-in, as the stock unit takes longer to decode.

I'd buy one also.

[Jim Thomas]

I'd buy one also, if it could be designed as a stand alone model and interface with the tuner.

[rdees]

Thanks for the input so far. Jim, the unit can be stand alone, all it needs is FM multiplex and power. Russ, having never seen a Conrad, is Bill's mod hardware or software? My unit has adjustable FM mutiplex sensitivity (via pot). The number of times you verify the data before you display it has a lot to do with it also. I am currently verifing PI and PTY four times before I display them. This would likely be able to be changed to two times via a jumper. I verify PS and RT twice. I must say that my prototype is extremely fast.

[Russ-PA]

I believe that it's a PI mod to enable faster decode of the PI, and I believe it was hardware. I don't know for certain, but it could be as simple as the difference between 2- and 4- hits you described. I'll have to ask him.

[Mike-CT]

The way Bill did it, you could either get the PS code or the PI code by changing chips. You couldn't get both. I know he did the mod to a few RDS Managers. He didn't do mine. I didn't really care since I had it running through my computer at that time. My RDS manager is now being used with a NAD tuner and the tuner has to be in monaural mode for the manager to see anything. I've not found a way for the RDS Manager to work when the tuner is in stereo.

[Russ-PA]

Mine was the PI enhancement, and it does work well. I did email Bill to inquire about further details and referenced this thread.

[bnollman]

The PI code mod was a chip I bought from a guy in the Czech Republic. I could dig out the info if interested. (see attached for a picture) It installed inside the Conrad and intercepted the data going to the display through a few DPDT switches. So either you got the Conrads standard display or the PI code from the chip. The PI code was very fast, the stock Conrad was painfully slow. The only real mod I ever did to the Conrad was to add a serial cable and some isolation capacitors (and a DB 9 cable) to use with the Esslinger software - which was faster than the Conrad display (and very nice to look at) and maybe a hair slower than the PI chip mod. I never mucked with software or stock hardware.

Finally we also tried the Katruud decoder (can't find a picture) that wasn't bad but I think had very short usable life span and I also had a guy named Earl in Michigan who designed his own RDS decoder to my specs (ok we fought a little over the end product but it is darned good unit ! - picture attached). That unit is still what I use for RDS exclusively.

[rdees]

Thanks to all for the info. Wow Bill! That's a BIG display!!

[rdees]

Well I got behind a little on this project, but things are moving again. Here are a few pictures of my progress.

[pjdyer]

Wonder what the status of this production is now? The size seems to be on a par with the XDR-F1HD.

73, Pat - WA5IYX

[rdees]

I'm am waiting on back panels. The finished unit will be 2.06 x 5.08 x 5.30 (HxWxD), so it's smalller than the XDR-F1HD.

Ray

[pjdyer]

OK, within an inch or so WxD. Do you have "mass production" in mind ? The shipping etc of something made in the US would be much simpler than Euro-based sources. With eyesight and dexterity at my age replicating/experimenting with SMT designs is unlikely :) 35 years ago even handling the 0.1" pin spacing on IC chips with caps and resistors with leads was a bit of a "challenge". I never got beyond etching single-sided PCB projects.

73, Pat - WA5IYX

[rdees]

I'm with you Pat. Some of my earlier designs were tube based with all point to point wiring! Back then you could buy a whole sack of tubes at the corner drug store cheaper than a single transistor would cost from either Allied of Lafayette. (I'm probably revealing my age to some of you.)

For those of you out there that are visually challenged now (like myself) check these people out:

http://www.epboard.com/index.html

They will even solder your parts on for you (for a fee). I'm using one of their products right now in my DSP radio project!

Anyway, to answer your question, the RDS decoders are not a kit. They will be completely assembled and tested.

[pjdyer]

My point-to-point soldering with VTs goes back to 1958 (ABSC Kits). I didn't get heavily involved in solid-state (TTL, etc) building until the early/mid 70s. I see that Mouser offers some IC chips in either SMT or DIP form for those of us who prefer sockets :)

This http://www.qsl.net/wa5iyx/images/rotenctun-a.gif is a collaborative effort at a circuit for enabling knob tuning of the XDR-F1HD. I've not been able to determine what the polling rate of the KB pushbuttons is so that the reset pulse rate from the 555 would be proper, etc. Similar circuitry shunting the preset (memory) up/down pushbuttons should permit a crude form of scanning selected frequencies for an Es event.

73, Pat - WA5IYX

[rdees]

The RDS decoders are now in stock and ready for shipment. You can find all of the information about the decoders here:

http://raydees.com/RDS_Decoder.html

Now that I have recovered my initial investment, the price has been lowered considerably!

[ei2gfb]

hi Ray are these still available, ive tried sending you a few emails

[rdees]

Yes, I have several left.