Main Menu. Manuals for Sony. AIR-7 8 Service manual. AIR-7 Instruction manual. AN-1 Instruction manual. AN-1 Service manual. AN-LP1 Service manual. CRF Service manual. CRF-1 Service manual. CRF-1 Supplement. CRF Circuit description new. CRFk Service manual. CRF-V21 Service manual.
ICB schematic. ICB Schematics. This must not be too large or it will interfere with the battery compartment to PCB contacts. C68 on the ripple filter input may also be worth changing. My attempts with parts more recently qualify as modern art at most - and that was with a suitable microscope. Incidentally, when the left output channel ultimately decided to stop working a few years later, the set had the remaining surface mount electrolytics replaced in early The old ones were checked with a capmeter during the process, they didn't measure up very well any more.
If power-on pop noise occurs, the primary suspect is C, which connects to an amplifier pin for pop noise suppression. Some pop noise under reduced voltages is normal though. Hollander in the Netherlands who wrote:. Resistances of only several kOhm has been found when probe tips were about a millimeter apart on the PCB. This caused wrong voltages on the varicaps in series with kOhm!
At first, not knowing what the real cause was, I replaced the varicaps of the FM-section Sony was so kind to supply me two for free , which helped for some months because I cleaned the PCB as well. Then I only cleaned the area around the varicaps, which also helped. Finally, when I realized the leakage, I replaced all 23 electrolytic capacitors except the one in the 14V DC-DC converter in the shielded box.
This seems to work! No bad FM-reception and unstable tuning anymore. This repair may easily damage your PCB. Do not try to unsolder the electrolytic capacitors, just crunch the capacitors so that you can unsolder the leads individually. Naturally, the FM section wasn't working. Varicap tuning voltage was high 14V due to no VCO output. I replaced the electrolytic capacitor on pin 23 of CX Initial tests were encouraging, showing the varicap tuning voltage was about 8VDC I had played with T10 tuning inductor.
And indeed, changing C69 turned out to be the solution to the "no FM" problem. However, you must not choose a capacitor that is physically too large, since then the battery-to-circuitboard contacts may no longer make proper contact. But as the saying goes, all is well that ends well, and now Ben's SW is working just fine! Be warned, however, that getting to C69 in the first place is a non-trivial task.
You need to take out the speaker easy , unclip the computer PCB and loosen the interconnecting ribbon cable fussy before you even have a chance to get the main PCB off the chassis.
Beware of the rod antenna wires, you may want to unsolder them their positions can be seen in the service manual. It has served me well for many years, until when I suffered two failures. I thought your readers would be interested in the two failures and the solutions. The specs hardly differ from those of the G , except for the number of presets non-volatile instead of just 20 that are lost if you leave out the batteries for too long , a variable attenuator and various other smaller improvements they're listed under "Pros" and "Cons".
The actual performance is said to be very similar to the SWG, so it seems there weren't many changes made in the HF portion. Concerning the name, I suspect it's supposed to say that the radio is a "G Revised". Since the GR is quite similar to the G below, much of the additional information and tips for this receiver should also apply to the newer model.
Service manual at RigPix local copy. These numbers were originally from the WRTH and partly posted on "group". Take them with a grain of salt, I personally don't really trust them. These are some rather good sensitivity figures for such a portable. I'd assume the G is similar. The reviewers noted that sensitivity is reduced on the EXT ANT input, another feature common with the previous model probably supposed to reduced IM problems on external antennas.
Apart from that, the "wide" measurements are surprisingly close to those obtained on a standalone SFRI filter 7. Okay, the receiver is apparently not that IM proof not a big surprise, given the G didn't fare so well there either , but it never has that good an image rejection.
Also, Passport to World Band Radio mentioned "adequate, but not excellent" image rejection. What the point of this should be is beyond me.
0コメント