¿ªÔÆÌåÓýFWIW i opened the filter compartment of my HQ 129 X? the crystal is in a holder similar to the one pictured in the SX110.? Itried tapping it.? Did not change frequency or have any effect on the phasing control.? as mentioned before the same ki d of holder is used in the RCA AR 88 . I have tapped that one too and found it made a slight noise but didn't seem to change its frequency. I think it's possible the electrodes may be a little loose.? The change in capacitance word affect the phasing control. -------- Original message -------- From: don Root <drootofallevil@...> Date: 11/3/22 5:31 PM (GMT-08:00) Subject: Re: [HallicraftersRadios] SX-110 Crystal Instability I¡¯m still curious; does the frequency jump suddenly from A to B, or does it ?settle for a bit on a variety of frequencies? or is it a slow change? Don VA3DRL ? From: [email protected] [mailto:[email protected]] On Behalf Of KW4H via groups.io ? An update.? I just did another crystal alignment and yet again found the right spot and re-confirmed the crystal oscillator frequency null is at 453.410 KHz.? However, there is no doubt that merely tapping on the crystal ¨C even a tiny bit ¨C causes the null point to noticeably change when the crystal is in use.? Now ¨C to be realistic ¨C that¡¯s what the crystal phasing control is for, and it won¡¯t end up in exactly the same place every time.? If it shifts a little, the phasing control ends up in a different position when you adjust it.? So, for a receiver this old ¨C meh ¨C and probably no one cared back then at this price point.? Nevertheless, I¡¯m going to try replacing the crystal with one that doesn¡¯t jiggle.? Just because. ? 73 ¨C Steve, KW4H ? From: <[email protected]> on behalf of Dan <pitfit@...> ? Perfect. ? Woulda thunk it? ? Thanks. ? Dan WB4GRA ?
|
