diff options
| author | Matthias P. Braendli <matthias.braendli@mpb.li> | 2021-03-05 21:22:57 +0100 |
|---|---|---|
| committer | Matthias P. Braendli <matthias.braendli@mpb.li> | 2021-03-05 21:22:57 +0100 |
| commit | df04f120a103976631047b08a35c310abfb7f604 (patch) | |
| tree | d64684081f6c7c921faff6772dcebf7dbefc5fe7 | |
| parent | ef4c18417684920726edaa6d0d01c85acc3a0abd (diff) | |
| download | picardy-df04f120a103976631047b08a35c310abfb7f604.tar.gz picardy-df04f120a103976631047b08a35c310abfb7f604.tar.bz2 picardy-df04f120a103976631047b08a35c310abfb7f604.zip | |
Some updates to improve PTT clicking
| -rw-r--r-- | README.md | 17 | ||||
| -rw-r--r-- | kicad/baseband.sch | 56 |
2 files changed, 43 insertions, 30 deletions
@@ -34,6 +34,12 @@ very first trial. Later, the external bandpass and 2x SPF5189Z were replaced by an internal bandpass with less insertion loss and a single SPF5189Z. + +*First 3cm QSO done with Picardy 2020 as IF transceiver on 2020-02-21* + +Using a Downeast Microwave 10368CK transverter. + + TODO ==== @@ -47,7 +53,7 @@ Open questions * Not tested, but plan B done (J306) * Use an additional PWM output for plan B? * Put sidetone volume setting before RV303? - * Hook up to LM375 BYPASS? + * Hook up to LM386 BYPASS? Issues ====== @@ -65,7 +71,14 @@ Issues * Unintended effect: removes LCD backlight * C319 and C326 are redundant * BC856W wrong footprint -* R327 upsets DC offset of audio amp, capacitive decoupling needed +* R327 upsets DC offset of audio amp, added 2.2uF capacitive decoupling in series with 1k + * PTT makes loud click, assemble with 100nF only, still loud + * Connected LM386 back to 8V, through 0 Ohm instead of 10 Ohm (was on 12V through 10 Ohm because DCDC noise). Still + loud. + * Investigate other muting schemes. + * Connecting BYPASS to GND generates click + * 2N3819 based muting according to G3YCC works better. + * Assemble 1k + 100nF for coupling, revert to 12k for R329, use 20k for R326 to slow down the transition a bit * 2m LPF from LimeRFE use values I don't stash * 20pF done with 2x 10pF * SW: ADC input for buttons looks messed up... diff --git a/kicad/baseband.sch b/kicad/baseband.sch index 7439dbe..33ebc72 100644 --- a/kicad/baseband.sch +++ b/kicad/baseband.sch @@ -1195,17 +1195,6 @@ Wire Wire Line 10800 4350 10650 4350 Connection ~ 10650 4350 $Comp -L power:GNDA #PWR0342 -U 1 1 5E53C532 -P 10800 4550 -F 0 "#PWR0342" H 10800 4300 50 0001 C CNN -F 1 "GNDA" H 10805 4377 50 0000 C CNN -F 2 "" H 10800 4550 50 0001 C CNN -F 3 "" H 10800 4550 50 0001 C CNN - 1 10800 4550 - 1 0 0 -1 -$EndComp -$Comp L Device:CP_Small C340 U 1 1 5E54E2B9 P 8150 6250 @@ -1318,18 +1307,6 @@ Wire Wire Line 7200 5800 7150 5800 Connection ~ 7200 5800 $Comp -L Device:R R329 -U 1 1 5E5DBA37 -P 10750 5550 -F 0 "R329" H 10820 5596 50 0000 L CNN -F 1 "12k" H 10820 5505 50 0000 L CNN -F 2 "Resistor_SMD:R_0603_1608Metric_Pad1.05x0.95mm_HandSolder" V 10680 5550 50 0001 C CNN -F 3 "~" H 10750 5550 50 0001 C CNN -F 4 "0" H 10750 5550 50 0001 C CNN "Need_order" - 1 10750 5550 - 1 0 0 -1 -$EndComp -$Comp L power:GNDA #PWR0340 U 1 1 5E604089 P 10650 6200 @@ -1364,7 +1341,7 @@ L Device:R R326 U 1 1 5E64AC63 P 10300 5750 F 0 "R326" H 10370 5704 50 0000 L CNN -F 1 "1.5k" H 10370 5795 50 0000 L CNN +F 1 "20k" H 10370 5795 50 0000 L CNN F 2 "Resistor_SMD:R_0603_1608Metric_Pad1.05x0.95mm_HandSolder" V 10230 5750 50 0001 C CNN F 3 "~" H 10300 5750 50 0001 C CNN F 4 "0" H 10300 5750 50 0001 C CNN "Need_order" @@ -2448,12 +2425,8 @@ Wire Wire Line 9300 5700 9400 5700 Wire Wire Line 9100 5700 9000 5700 -Text GLabel 10750 5400 1 50 Input ~ 0 -+8V Wire Wire Line 10600 5200 10650 5200 -Wire Wire Line - 10750 5700 10650 5700 Connection ~ 10650 5700 Wire Wire Line 10650 5700 10650 5750 @@ -3340,4 +3313,31 @@ Wire Wire Line Connection ~ 10550 600 Wire Wire Line 10550 600 10750 600 +Wire Wire Line + 10750 5700 10650 5700 +$Comp +L Device:R R329 +U 1 1 5E5DBA37 +P 10750 5550 +F 0 "R329" H 10820 5596 50 0000 L CNN +F 1 "12k" H 10820 5505 50 0000 L CNN +F 2 "Resistor_SMD:R_0603_1608Metric_Pad1.05x0.95mm_HandSolder" V 10680 5550 50 0001 C CNN +F 3 "~" H 10750 5550 50 0001 C CNN +F 4 "0" H 10750 5550 50 0001 C CNN "Need_order" + 1 10750 5550 + 1 0 0 -1 +$EndComp +$Comp +L power:GNDA #PWR0342 +U 1 1 5E53C532 +P 10800 4550 +F 0 "#PWR0342" H 10800 4300 50 0001 C CNN +F 1 "GNDA" H 10805 4377 50 0000 C CNN +F 2 "" H 10800 4550 50 0001 C CNN +F 3 "" H 10800 4550 50 0001 C CNN + 1 10800 4550 + 1 0 0 -1 +$EndComp +Text GLabel 10750 5400 1 50 Input ~ 0 ++8V $EndSCHEMATC |