From: JohnAdams@johna.ds5200.gradyn.co.uk Newsgroups: rec.radio.shortwave Subject: Fine Tuning for the Sangean 803A > > Hi, > Could someone please repost the information about fine tuning the Sangean 803A. > I'm afraid I missed it. > > Thanks alot. > > Monte Olsen Path: osiris.wu-wien.ac.at!usenet From: JohnAdams@xxx Newsgroups: rec.radio.shortwave Subject: Fine Tuning for the Sangean 803A Date: Thu, 14 Apr 94 07:53:34 PDT Organization: Vienna University of Economics and Business Administration Lines: 75 Message-ID: <2oipo8$o9b@osiris.wu-wien.ac.at> NNTP-Posting-Host: nestroy.wu-wien.ac.at Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Newsreader: NEWTNews & Chameleon -- TCP/IP for MS Windows from NetManage These instructions describe how I modified my Sangean 803A so that the BFO Pitch acts as a fine (approximately +/- 5kHz) tuning control on all but the FM band. The instructions are as detailed as my brain permits of. The tools required are a small-to-medium Philips or posidrive screwdriver, a small soldering iron, some solder and a means of removing surplus solder (e.g a solder sucker or a few inches of desoldering braid). 1. Make sure that you have a note of any preset frequencies you have pro- grammed into the memories. Turn the radio off. Remove all external connections (e.g. headphones, external power, external aerial) from the radio. Close down and clip down the radio's own whip aerial. 2. Take the radio to a well-lit worksurface. Put something on the worksur- face to prevent damage to it or to the radio. Put the radio face-down on the table so that the base of the radio is nearest to you. Remove the battery compartment door and then remove the batteries. Unscrew the six screws which retain the back panel of the case. Five are down recesses in the back panel at the top left, top right, bottom right and bottom-center-right. The sixth is in the left corner of the battery compartment. Try to leave the screws in their respective holes. You can feel when the screws have been unscrewed enough when they don't seem to be coming out anymore! Gently free the back panel from the rest of the radio case but don't try to pull it away from the radio. There is an awkward wire connecting the whip aerial to the rest of the radio! Once the back panel is free, lift it about half an inch, and then swing it back away from you, rotating it anti-clockwise in a way that keeps the left-hand side of the back panel over the radio and hence the aerial wire safe! 3. Set the lid down and examine the circuit board which lies behind the BFO ON/OFF switch. The BFO ON/OFF switch is mounted directly onto this circuit board and you will see the switch's six solder pads arranged as two rows of three. The row to work on is the row furthest from you. Calling these, from left to right, 1, 2 and 3, use the solder removing gear to remove all solder from pad 3. This should leave pin 3 visibly isolated from the surrounding circuit board. Next, solder pins 1 and 2 together - probably most easily done by melting the solder on both pins by spreading the soldering iron across the two and then introducing some extra solder to bridge them - the sort of thing we usually do by mistake. 4. That's it. Replace the back, taking care not to catch the awkward wire in the case - or anywhere else. Do up the six screws evenly, i.e. do them up until they are all just starting to resist you, checking that the back panel is fully onto the rest of the case as you go, then give each screw a little bit more of a turn. Don't leave them loose, but don't do them any tighter than that! Its only plastic! 5 Restore batteries and any other items detached in step 1. You now have an 803A+. I'm sure that I needn't point out that the Establishment would tear you (and your warranty) limb from limb for fiddling inside their creation - particular- ly as it was particularly short-sighted of them not to have done this them- selves - but there, hind-sight is a wonderful thing. Do remember that the fine tune is always in use on AM, so at its extreme you'll be 5kHz off the indicated frequency. Talking of indicated frequency, you might find that stations appear to be on tune when the BFO control is slightly off its mid-position. Well no synthesiser is dead on frequency - although my Sangeans are within 200Hz of true. The point is that this fine tune lets you receive stations optimally and this won't always be on the centre frequency. One of the best features of having a fine tune is that a whistle interfering with a station you're tuned directly onto can usually be nulled out by using the fine tune to slip slightly off frequency. Neverthe- less, if you want an 803A++, get back into the set and use a proper trimming tool to adjust T111 to bring the radio bang on tune! John Adams