I have built a software controlled receiver based on the RF section from a Grundig YB400 (YB 400, Yacht Boy
400) radio; I have the schematics from the Grundig service manual (kindly posted to a web forum) but I need to locate the remainder of the service manual for component call-outs and alignment data among other things. I have generated some call-out graphics from tedious tracing under a magnifier but many components are hidden under shields which I won't remove until necessary and tracing the remainder of the rig would take quite a stretch of time.
Doe anyone have this book in electronic or hardcopy form?
Software Controlled Radio or Software *Defined* Radio ? If the latter, I would have thought that a Yacht Boy would not have had the front-end performance to sufficiently showcase an SDR module. Just interested. Sorry, don't have the service info for that model.
ANd the guy hasn't designed anything, he's stealing the design, and hasn't even gotten that far, or else he'd not be looking for the schematic.
When I got an older Grundig shortwave receiver last fall at a community sale, it wasn't long before I had the cover off, and at least had a general layout of the circuit, just by looking at it. If someone is going to steal a design, at least they should do thw work.
Please refrain from unwarranted vitriol; in my post I stated that I had the schematics, I just hoped to find the rest of the book. This is a personal project and I should have written 'used the RF section from a YB 400' rather than 'based on the RF section from a YB 400'. Aren't there any homebrewers here?
I must mention that I tried to purchase a manual from 'Eton', the current owner of the Grundig radio line and I was told that they don't have this manual, that it was unavailable to them. Ergo, my usenet request. The service manual was published in Germany and was not restricted.
Indeed; if you check the archives you'll find my post to that NG with this request some weeks ago. It seems to me more likely that folks involved in depot repair and service will potentially have the manual and are more likely to read this NG...
Yes, I am both licensed, and an old-school home brewer, which is why I was interested in exactly what you were talking about, and what you were trying to do with it. This month's RadCom has an article which actually deals with the principle of what it would seem that you are trying to do, using an old FT290 as a VHF front end for an SDR module - that's assuming that we are talking SDR here, a point which you haven't cleared up yet.
I designed a digital section to control the pll 1st LO, filter selection, BFO, and misc. power and control lines with provision for additional signals as the design progresses. I modified the RF section to accommodate my digital design, removed superfluous components no longer used and added modules at appropriate places where real estate permitted, changed the antenna input circuits and provided a 50 ohm bnc input. The RF section and digital section are separately encased in faraday cage shields, all dc lines are bypassed and filtered, serial i/o is ferrite choked and ground straps are liberally used. I have work to do yet to quench processor clock harmonics and mcu conducted RFI on a small number of i/o lines between the modules (I've reduced this RFI by about 10db since I started...). I may need to do some software-based autonotching to move the birdies out of the passband dynamically.
I download operating code over an rs232 port which also serves as the control interface and I'm writing a comprehensive VT100-graphics based control program for a systems-agnostic way to operate the receiver.
I will be posting a link to the website documenting this project soon (in rec.radio.amateur.homebrew) and will provide online access to the receiver with realtime RTP audio streaming.
They seem to have a pretty good stock of manuals and schematics for European made radios, including Grundig. The Grundig page lists the YB-400, but don't know if it's the complete manual or just the schematic. Six pages, if that helps.
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
Thanks for the lead; I know that the service manual has at least
20 pages and the schematics as foldouts occupy 6 A4 pages so he must have only schematics. Also, he lists the year of introduction of the YB400 as '81 which is a bit odd since many ICs it uses weren't produced until the late '80s :) However, I will email him and inquire further.