Heathkit Service Bulletins - HD-1530 (Complete)

[Joseph W Lutz]

                        January 16, 1987
HD-1530                                         Bulletin No:
Touch-Tone(R) Decoder                           HD-1530-1

        Won't Indicate Valid A, B, C and D Tones Except At Very Low
                                  Audio Input Levels

In the input circuitry of the DTMF receiver at U103, change:

        R107 from a 100 kilohm resistor to a 47 kilohm resistor [PN
6-473-12].

Install this change only when needed.
----------------------------------------------------------------------------------------------------------------
Thats everything I hold up to 1989 that covers the HD-1530.  Enjoy!
----------------------------------------------------------------------------------------------------------------


73 de Joe  W7LPF/4  [NNN0KUU]
QWCA - SOWP - NCVA - FISTS - RCC
Gordonsville, Va 22942 [Orange Co]

--- --- --- --- --- --- --- --- --- --- --- --- --- --
To subscribe: listserv at listserv.tempe.gov
and in body: subscribe HEATH yourfirstname yourlastname
To unsubscribe:  listserv at listserv.tempe.gov
and in body: signoff HEATH
Archives for HEATH: http://www.tempe.gov/archives
--- --- --- --- --- --- --- --- --- --- --- --- --- --