rekado [Sat, 18 Apr 2015 17:01:57 +0000 (19:01 +0200)]
do not attenuate tuner output at all
rekado [Fri, 10 Apr 2015 04:45:50 +0000 (06:45 +0200)]
explain how to keep schematics and board in sync
rekado [Fri, 10 Apr 2015 04:40:36 +0000 (06:40 +0200)]
board: place and connect C450
rekado [Fri, 10 Apr 2015 04:19:01 +0000 (06:19 +0200)]
place C450 on board, connected to external pin
C450 must be placed after pin CONN403 (BLEND) as it should be placed on
the board and is not part of the off-board assembly (unlike the dual
potentiometre mixing RETURN_HIGH and RETURN_LOW).
rekado [Sun, 5 Apr 2015 19:21:10 +0000 (21:21 +0200)]
board: load updated netlist, remove pin
rekado [Sun, 5 Apr 2015 19:20:05 +0000 (21:20 +0200)]
connect nets XOVER and PREAMP_2
rekado [Sun, 5 Apr 2015 19:06:06 +0000 (21:06 +0200)]
board.pcb: update to latest file format
rekado [Sun, 5 Apr 2015 19:04:03 +0000 (21:04 +0200)]
remove superfluous pin
rekado [Sun, 5 Apr 2015 19:03:26 +0000 (21:03 +0200)]
add pin for preamp2 out / xover in
rekado [Sun, 1 Mar 2015 10:48:32 +0000 (11:48 +0100)]
add TODO
rekado [Sun, 1 Mar 2015 10:46:46 +0000 (11:46 +0100)]
add archive of old drafts
rekado [Sun, 1 Mar 2015 10:46:12 +0000 (11:46 +0100)]
add parts map
rekado [Sun, 1 Mar 2015 10:41:49 +0000 (11:41 +0100)]
add old enclosure drawings
rekado [Thu, 8 Aug 2013 08:21:56 +0000 (16:21 +0800)]
swap crossover output
rekado [Wed, 7 Aug 2013 11:48:27 +0000 (19:48 +0800)]
add indicator LED for crossover
rekado [Mon, 5 Aug 2013 10:37:37 +0000 (18:37 +0800)]
add output jacks
rekado [Sun, 4 Aug 2013 14:12:07 +0000 (22:12 +0800)]
add missing coupling capacitor
rekado [Sun, 28 Jul 2013 02:33:00 +0000 (10:33 +0800)]
colours and line thickness
rekado [Fri, 26 Jul 2013 14:29:57 +0000 (22:29 +0800)]
a few more fixes before production
- power switch and connector on the same side
- add labels for clarification
- clean up help lines
rekado [Thu, 25 Jul 2013 03:41:35 +0000 (11:41 +0800)]
ready for production?
rekado [Mon, 22 Jul 2013 23:55:22 +0000 (07:55 +0800)]
text: add on/off switch
rekado [Mon, 22 Jul 2013 23:43:46 +0000 (07:43 +0800)]
board holes to "holes" layer
rekado [Sat, 20 Jul 2013 14:56:10 +0000 (22:56 +0800)]
add status LED
rekado [Sat, 20 Jul 2013 14:33:04 +0000 (22:33 +0800)]
various changes
- position and spacing of jacks
- spacing of potentiometres
- more dimension annotations
- hole for DC jack
rekado [Fri, 19 Jul 2013 13:53:39 +0000 (21:53 +0800)]
drill pattern, first draft
rekado [Fri, 19 Jul 2013 13:53:02 +0000 (21:53 +0800)]
drawing of Hammond enclosure
rekado [Thu, 24 Jan 2013 23:31:24 +0000 (07:31 +0800)]
update component names / silk screen
rekado [Tue, 8 Jan 2013 14:24:55 +0000 (22:24 +0800)]
3 mounting holes: M2x0.4
rekado [Wed, 2 Jan 2013 13:23:50 +0000 (21:23 +0800)]
increase mount hole diameter
rekado [Wed, 2 Jan 2013 10:02:56 +0000 (18:02 +0800)]
reduce gain of melody preamp?
rekado [Wed, 2 Jan 2013 10:02:38 +0000 (18:02 +0800)]
move cap away from drill hole
rekado [Tue, 1 Jan 2013 11:26:19 +0000 (19:26 +0800)]
remove out pins to -Vcc from board
rekado [Tue, 1 Jan 2013 10:15:03 +0000 (18:15 +0800)]
remove outdated comment
rekado [Mon, 31 Dec 2012 09:40:04 +0000 (17:40 +0800)]
increase route to pin clearance
rekado [Mon, 31 Dec 2012 09:35:38 +0000 (17:35 +0800)]
simplify routing of melody return cap
rekado [Sat, 29 Dec 2012 14:42:49 +0000 (22:42 +0800)]
redesign
- less space between resistors
- removed trim pots
- removed one signal buffer
- routed Vcc through transistor pins (maybe change that later)
rekado [Sat, 29 Dec 2012 12:17:03 +0000 (20:17 +0800)]
bypass contacts are wired on the switch, off-board
rekado [Sat, 29 Dec 2012 10:43:36 +0000 (18:43 +0800)]
remove melody buffer (preamp is buffered); remove trim pots
rekado [Fri, 28 Dec 2012 12:28:36 +0000 (20:28 +0800)]
correct name
rekado [Fri, 28 Dec 2012 12:28:01 +0000 (20:28 +0800)]
connect only one of the jack switches
rekado [Thu, 27 Dec 2012 14:13:17 +0000 (22:13 +0800)]
reduce gain/distortion
there still is some distortion which could possibly be eliminated by
increasing the resistor some more.
rekado [Thu, 27 Dec 2012 14:12:53 +0000 (22:12 +0800)]
don't roll off low frequencies in bass preamp
rekado [Thu, 27 Dec 2012 00:20:49 +0000 (08:20 +0800)]
pins to connect offboard blend pot
rekado [Thu, 27 Dec 2012 00:16:02 +0000 (08:16 +0800)]
put inputs on -Vcc when nothing is connected
rekado [Wed, 26 Dec 2012 12:28:30 +0000 (20:28 +0800)]
improve coupling at mixer
rekado [Wed, 26 Dec 2012 12:27:48 +0000 (20:27 +0800)]
add coupling caps to return; remove from mixer
rekado [Wed, 26 Dec 2012 10:11:08 +0000 (18:11 +0800)]
update all coupling caps to 10uF
this is to ensure that the voltage across the cap is low at all
frequencies we care about.
rekado [Wed, 26 Dec 2012 10:05:01 +0000 (18:05 +0800)]
clean up middle section
rekado [Wed, 26 Dec 2012 10:04:35 +0000 (18:04 +0800)]
remove coupling caps
rekado [Sun, 23 Dec 2012 07:25:37 +0000 (15:25 +0800)]
connect reference voltage via resistor; reduce cap value
rekado [Sat, 1 Dec 2012 16:28:37 +0000 (00:28 +0800)]
replace power filtering resistor with inductor
rekado [Mon, 26 Nov 2012 14:01:45 +0000 (22:01 +0800)]
replace another JFET with NPN transistor
rekado [Mon, 26 Nov 2012 13:57:30 +0000 (21:57 +0800)]
replace JFET with NPN transistor
rekado [Mon, 26 Nov 2012 10:54:17 +0000 (18:54 +0800)]
place and connect transistor in tuner mixer
rekado [Mon, 26 Nov 2012 00:18:47 +0000 (08:18 +0800)]
add NPN transistor to make mixer active
rekado [Fri, 23 Nov 2012 10:30:01 +0000 (18:30 +0800)]
add transistor after bass blend pots
rekado [Fri, 23 Nov 2012 10:15:51 +0000 (18:15 +0800)]
update board to latest schematic changes
rekado [Fri, 23 Nov 2012 10:05:04 +0000 (18:05 +0800)]
reminders to add buffers/active mixers
rekado [Fri, 23 Nov 2012 10:04:29 +0000 (18:04 +0800)]
add shunt resistor to output
rekado [Thu, 22 Nov 2012 15:07:13 +0000 (23:07 +0800)]
update board
rekado [Thu, 22 Nov 2012 15:07:03 +0000 (23:07 +0800)]
add jumper to connect Vcc nets
rekado [Thu, 22 Nov 2012 13:38:02 +0000 (21:38 +0800)]
move power rails filtering to power supply
rekado [Fri, 23 Nov 2012 02:32:43 +0000 (20:32 -0600)]
rename power connector to make it appear on PCB
rekado [Thu, 22 Nov 2012 00:06:01 +0000 (08:06 +0800)]
more biasing with reference voltage
rekado [Thu, 22 Nov 2012 00:04:32 +0000 (08:04 +0800)]
adjust value and size of support caps
rekado [Thu, 22 Nov 2012 00:00:10 +0000 (08:00 +0800)]
power supply filtering
rekado [Wed, 21 Nov 2012 12:10:10 +0000 (20:10 +0800)]
use this expensive voltage reference instead of a voltage divider
rekado [Tue, 20 Nov 2012 11:36:24 +0000 (19:36 +0800)]
first complete layout draft
rekado [Tue, 20 Nov 2012 09:53:41 +0000 (17:53 +0800)]
remove DI box
I don't really need a DI box all the time. It complicates the circuit,
draws more power, and requires more space.
An external DI box can be connected to the mono output for the same
result.
rekado [Mon, 19 Nov 2012 14:57:37 +0000 (22:57 +0800)]
update board
rekado [Mon, 19 Nov 2012 13:03:57 +0000 (21:03 +0800)]
update board
rekado [Mon, 19 Nov 2012 13:03:03 +0000 (21:03 +0800)]
add pin to bass blend pot
rekado [Mon, 19 Nov 2012 10:46:03 +0000 (18:46 +0800)]
ignore more files
rekado [Mon, 19 Nov 2012 10:43:43 +0000 (18:43 +0800)]
remove outdated notice
rekado [Mon, 19 Nov 2012 10:41:32 +0000 (18:41 +0800)]
hide footprint attribute
rekado [Mon, 19 Nov 2012 10:32:27 +0000 (18:32 +0800)]
add virtual ground IC
rekado [Mon, 19 Nov 2012 00:15:48 +0000 (08:15 +0800)]
replace tuner trim pot with fixed resistor
rekado [Mon, 19 Nov 2012 00:13:51 +0000 (08:13 +0800)]
set graphical=1 for off-board components
rekado [Mon, 19 Nov 2012 00:12:12 +0000 (08:12 +0800)]
remove trim pot before DI box
rekado [Mon, 19 Nov 2012 00:02:23 +0000 (08:02 +0800)]
add connectors to output signals
rekado [Sun, 18 Nov 2012 15:00:36 +0000 (23:00 +0800)]
update board
rekado [Sun, 18 Nov 2012 14:52:32 +0000 (22:52 +0800)]
change switch footprint to generic connector
rekado [Sun, 18 Nov 2012 14:22:14 +0000 (22:22 +0800)]
simplify the crossover bypass
rekado [Sun, 18 Nov 2012 13:21:23 +0000 (21:21 +0800)]
effects inserts for bass channels
rekado [Sun, 18 Nov 2012 10:29:00 +0000 (18:29 +0800)]
add pins for bass effects insert
rekado [Sun, 18 Nov 2012 09:58:04 +0000 (17:58 +0800)]
add connector for inputs
rekado [Sun, 18 Nov 2012 09:42:07 +0000 (17:42 +0800)]
remove default footprint from stereo jack symbol
rekado [Sun, 18 Nov 2012 09:39:13 +0000 (17:39 +0800)]
merge preamp circuits
rekado [Sun, 18 Nov 2012 08:21:32 +0000 (16:21 +0800)]
add connector for tuner output and melody insert
rekado [Sun, 18 Nov 2012 08:08:46 +0000 (16:08 +0800)]
simplify melody send/return
I no longer want to use two mono sockets for separate send and return
routing. A single stereo jack for effects insert is just as fine and
easier to implement. I also no longer care for an effects blend
potentiometer that determines how much of the unprocessed signal is to
be blended with the return signal. Controlling the effect intensity is
the external device's job.
rekado [Sat, 17 Nov 2012 15:02:47 +0000 (23:02 +0800)]
crossover routing
rekado [Sat, 17 Nov 2012 08:22:24 +0000 (16:22 +0800)]
start routing preamps
rekado [Sat, 17 Nov 2012 04:22:39 +0000 (12:22 +0800)]
reduce board size
rekado [Sat, 17 Nov 2012 03:31:30 +0000 (11:31 +0800)]
correct power supply of IC401
rekado [Sat, 17 Nov 2012 02:48:38 +0000 (10:48 +0800)]
use BOURNS 3296w footprint for trim pots
The footprint was created with the bourns_3266-3296.pl perl script by
David Griffith using John C. Luciani Jr's footprint creation library.
rekado [Sat, 17 Nov 2012 02:26:13 +0000 (10:26 +0800)]
roughly align both preamp sections
rekado [Fri, 16 Nov 2012 15:06:13 +0000 (23:06 +0800)]
begin PCB layout
rekado [Fri, 16 Nov 2012 15:05:25 +0000 (23:05 +0800)]
rename nets to ensure they are separate
rekado [Fri, 16 Nov 2012 14:28:54 +0000 (22:28 +0800)]
replace CK05 cap footprint with ACY100
rekado [Fri, 16 Nov 2012 14:24:27 +0000 (22:24 +0800)]
RCY300P --> RCY150P for 100uF caps