home *** CD-ROM | disk | FTP | other *** search
- From parnass@cbnewse.cb.att.com Sun Aug 1 14:25:14 1993
- Newsgroups: alt.radio.scanner
- From: parnass@cbnewse.cb.att.com (Bob Parnass, AJ9S)
- Subject: Re: BC855XLT
- Organization: AT&T Bell Laboratories, Naperville, IL
- Date: Thu, 29 Jul 1993 18:43:19 GMT
- Summary: repost of 855xlt mods for 100 channels and full 800 MHz
-
-
- Here is a repost of John Wilkerson's article from Feb 1993
- on modifying the Uniden 855XLT:
-
-
- DISCLAIMER: This article is listed for the
- technically curious. No guarantees are
- stated that the mods listed below will
- work on all scanners of this model.
-
-
- UNIDEN BC-855XLT MODIFICATIONS
- Scope of modifications:
- [1] Allow continuous 800 MHz receive.
- [2] Increase channel capacity from 50 to 100 ch.
- 1 2 3 4
- :------------------------------------------:
- | I p p p p o o o o o o |
- :----------| I | | | | |
- | [I] | | X X <-- CUT |
- | [I] D201 | | | | |
- | [I] oooooo | | | | |
- | I d d d d |
- | I------/\/\/\--------|--| |
- | |
- | ADD 4.7K - 22K Ohm (10K works) |
- | 1/4 watt carbon resistor between |
- | diode D201 and lower connection |
- | of Jumpers 3 & 4 |
- | Jumper 3 - 100 ch. Jumper 4 - 800 MHz |
- |-----------------------------------------------------|
- 1. Remove 5 screws from bottom of scanner case.
- 2. Carefully separate case top and bottom.
- 3. Unplug connector to the internal speaker.
- 4. Locate diode D201 and 4 jumpers near edge of circuit board.
- 5. Cut the 3rd and 4th jumpers near the middle and fold
- downwulate leads, if necessary.
- 6. Connect the lower part of jumper 3 & 4 to one end of a 10K
- Ohm 1/4 watt carbon resistor, insulate all exposed leads.
- 7. Connect the other resistor lead to the lower connection of
- diode D201, DO NOT cut any leads on D201.
- 8. Make sure all exposed leads aren't touching any other
- connections, insulate as required, tack in place
- with a dab of RTV silicone, or low temp hot glue.
- 9. Reassemble scanner, make sure to plug the speaker back in.
- You should now have a scanner with 100 chs. numbered 01-00
- in 5 banks of 20 ch. and continuous 800 MHz coverage.
-
-
- WARNING!!! Doing the mod to jumper 4 REMOVED 75 percent of the 800 MHZ
- Band on my Scanner. Replaciing the jumper restored the
- coverage to design limits, without harming the Scanner.
-
- My serial # is 25021343.
-
- I suspect different boards have been used in this scanner.
-
- ADDITION: My scanner had the jumpers depicted. However, there were 2
- more jumpers after those depicted. Disregard any additional
-
-
- --
- ___ _ _ __ _
- ( > / _// ' ) / // /
- __/______/_ ____ / / / / o // /_ _ __ _ ________
- / / (_) / /_/ / <_ /___ o (_(_/ <_</_/ <_</_/ (_/_)_(_) / / <_
- <_/ johnw@bluemoon.use.com jwilkerson@delphi.com
-
- --
- ==============================================================================
- Copyright 1993, Bob Parnass, AJ9S
- AT&T Bell Laboratories - parnass@ih4gp.att.com - (708)979-5414
-
-