Belcom LS120l radio (crystal filter)

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Sparkey55
    Badcaps Legend
    • Jan 2010
    • 1523
    • USA

    #21
    Re: Belcom LS120l radio (crystal filter)

    Originally posted by eccerr0r
    Would that affect the crystal vibration frequency with additional mass?
    That would depend on how much was used. I would think that any lose carbon particles would try to settle on the quartz blank and cause drift.

    Comment

    • eccerr0r
      Solder Sloth
      • Nov 2012
      • 8701
      • USA

      #22
      Re: Belcom LS120l radio (crystal filter)

      Do you have the old one removed or going to wait until you get the "new" one?

      Comment

      • llonen
        Badcaps Veteran
        • Sep 2014
        • 495
        • hampshire

        #23
        Re: Belcom LS120l radio (crystal filter)

        I have had the defective one removed for inspection, most of the time it tests out fine on a scope and rf signal gen, its an intermittent problem and not one I am inclined to attempt dismantling of the unit as it is sealed with solder. For now its back in the radio, with regards to the one from ebay most if not all those old boards were single sided non plated through holes so am hoping its not been too mangled on removal. Will test before installation, along with several USA sellers for now this is the only one i have been able to find.
        Last edited by llonen; 05-20-2018, 02:16 AM.

        Comment

        • stj
          Great Sage 齊天大聖
          • Dec 2009
          • 31007
          • Albion

          #24
          Re: Belcom LS120l radio (crystal filter)

          cut the top off with a dremel?

          Comment

          • llonen
            Badcaps Veteran
            • Sep 2014
            • 495
            • hampshire

            #25
            Re: Belcom LS120l radio (crystal filter)

            Well the crystal lattice filter has arrived and the foot print seems to match the query defective filter so will probably not need to modify the PCB. I started re capping the PA stage and re making the solder joints, looking at the general state of the radio I will probably continue the process I also have some fer-rite beads on order.

            Potentially bad capacitors notwithstanding the boards in the radio appear to be a mass of bad solder joints, well the through hole links / pins anyway so will probably end up as a full and much needed service. Will most likely need re aligning as well, I fully intend to leave the VCO block well alone as this is a known pain in the ass to setup and since it appears to work well I will not be touching it unless absolutely needed.

            Will update as work progresses, I have a lot of customers work in though so this keeps getting pushed back as it is one of my radios lol.

            Comment

            • kc8adu
              Super Moderator
              • Nov 2003
              • 8832
              • U.S.A!

              #26
              Re: Belcom LS120l radio (crystal filter)

              got a pic of the whole board?
              if this is an old uniden board it is easy to hack it for 10m

              Comment

              • llonen
                Badcaps Veteran
                • Sep 2014
                • 495
                • hampshire

                #27
                Re: Belcom LS120l radio (crystal filter)

                I can put up a pic of the whole board(s) of which there are several, the unit is not a Uniden chassis and includes quite a lot of discreet logic on one of the boards. It is however a very easy mod for 10 meters, one I carried out quite some years ago when the radio was obtained. I have had quite a lot of work come through and regrettably have yet to complete work on this set.

                Rf board now recapped and fer-rite beads inserted where required, remounting the board is next, then carry on with recapping the main board(s).

                pics as promised although not actually pics from my boards but you get the general idea of whats inside.
                Attached Files
                Last edited by llonen; 07-21-2018, 08:17 PM.

                Comment

                Related Topics

                Collapse

                • shelby5041
                  clock radio / radio lifespan?
                  by shelby5041
                  hi
                  ive got a modern digital clock radio approx 15yrs old

                  my question is how long can a clock radio or a simple radio last ss farcas operating hours?

                  since elec components have limited hour lifecspan i would imagine the radio or clock radio would eventually fail.

                  the reason i ask is because i have my clock radio on radio function 24/7 for the past 7 years and its still working fine....i leave the radio on ..never turn off past 7years...thats approx 60000 hours

                  it uses very little power just a few watts i would imagine that may have something...
                  09-14-2024, 03:30 AM
                • UserXP
                  Vintage SONY Digital Clock Radio ICF-C12W no audio
                  by UserXP
                  Dear all,

                  I have this old radio clock by Sony from the early 80s, I guess. The clock display works, but is dim, the function board appears to be OK - but the radio unit shows no signs of life. It doesn't produce a single noise, crack or anything from either FM or AM band. It's like it doesn't even power up.
                  i opened the radio and it is full of some TRACON gray capacitors. They only have their negative strip printed, voltage and capacitace markings - no series, no temperature marking, nothing else.
                  My question is, do you know of this brand of capacitors and how bad are...
                  07-21-2025, 08:35 AM
                • praveenramavath
                  Majority PETERHOUSE GRADUATE Internet Radio (Auna Silver Star) - Stuck at boot "Welcome" Screen
                  by praveenramavath
                  Hello All,

                  I have an issue with my Majority PETERHOUSE GRADUATE Internet Radio, it keeps rebooting at the boot logo Welcome screen. I have an another forum active in other website but due to lack of response I am posting the same here. I am positing a link below that has pictures including all the troubleshooting I have tried, appreciate if someone can take a look and give me any suggestions.

                  https://www.hifivision.com/threads/m...-screen.98243/


                  Troubleshooting Summary: Majority Internet Radio - Flash Chip
                  ...
                  04-26-2025, 09:08 AM
                • Document Archive
                  HP EliteDesk 800 G3 + OfficeConnect OC20 2x2 Dual Radio 802.11ac (RW) Access Point EliteDesk 800 i7-7700T Specification for Upgrade or Repair
                  by Document Archive
                  This specification for the HP EliteDesk 800 G3 + OfficeConnect OC20 2x2 Dual Radio 802.11ac (RW) Access Point can be useful for upgrading or repairing a desktop PC that is not working. As a community we are working through our specifications to add valuable data like the EliteDesk 800 G3 + OfficeConnect OC20 2x2 Dual Radio 802.11ac (RW) Access Point boardview and EliteDesk 800 G3 + OfficeConnect OC20 2x2 Dual Radio 802.11ac (RW) Access Point schematic. Our users have donated over 1 million documents which are being added to the site. This page will be updated soon with additional information....
                  09-12-2024, 02:00 PM
                • Omron
                  Kenwood KDC 3051G Car Radio permanently stuck in Demo Mode please help
                  by Omron
                  Hello Guys! I have trouble with my car radio Kenwood KDC 3051G I hope someone more knowledgeable can help me, I tried everything in my power that I stumbled upon online.

                  My radio is permanently in demo mode, it says Press Volume Knot Cancel Demo and when I press it nothing happens.

                  - Tried to unplug radio and plug it back in into power,

                  - Tried to reset radio by holding reset button key for 5,10,30 seconds while in power and without power, plugging it back in, it wouldn't work.

                  - Tried to hold 3,6 while turning it back on and then pressing 1,2...
                  05-23-2024, 01:27 PM
                • Loading...
                • No more items.
                Working...