Build Thread is still under construction. Please ask any questions you have on this thread so we can add the detail needed.
Use FREQ500 audio path build map link below to place and tick off all parts.
FREQ500 AUDIO PATH KIT build map
http://www.jlmaudio.com/builds/maps/freq500audiomap.html
Photos of finished FREQ500 Audio path pcb.
FREQ500 Audio path pcb can be tested by itself by fitting a jumper shunt to pin 5 & 6 in the centre of the 10 pin header.
Then fitting a second jumper to TP1 will switch the pcb from bypass to audio path which should give the same level audio output.
Notes and Errata
5 of the 150k have been changed to 330k to balance the green led brightness better to the red led brightness.
Map shows which 5 of 150k resistors are now 330k.
Lo filter pcb need one white wire soldered under neath the pcb to link ground plane on the pcb.
Use FREQ500 filter path build map link below to place and tick off all parts that can be fitted before following the photos below.
FREQ500 FILTER build map
http://www.jlmaudio.com/builds/maps/freq500eqmap.html
Fit all resistors, ic sockets and caps in order shown on the build map link above
Cut off unused toggle switch legs as shown in photos below
Fit toggles flat to the pcb and solder in place
Fit all 10k dual pots with pull switch flat onto pcb and solder in place
Fit all CF frequency caps and solder in place and plug all opamps in th correct way around with all pin 1 dots closest to the front pots.
If building a matched pair make sure the matched pair of CF caps go to the same positions in each FREQ.
Snap v grooved pcb in half or 6 and fit the 10 pin right angle headers and solder in place
Snap into 6 if you haven't already and get leds, metal bracket and front panel ready to assemble
Stainless steel bracket fits perfectly into recess on rear of front panel
Looking at front of the pcbs cut of locate tab from pots on the right side of the pcb
Fit top hi pcb with left pot locate tab into stainless steel bracket and fit nuts only hand tight (we no longer use washers)
Bend one orange and one clear led short legs downwards to just less than 90degrees
Hold long legs with small pliers about 4mm away from plastic led and bend downwards to just less then 90degrees
The short K leg once bent will now look like it is the longer leg.
Fit the short (now long) K leg in the hole closest to the edge of the pcb marked K and other leg in hole behind marked A
Drop the orange and clear leds into the front panel holes.
Solder one leg of each led and check sitting correctly and not shorting to anything before soldering the 2nd leg.
Repeat this for HI MID, MID, LO MID & LO pcbs
Undo the hand tight nuts & remove the HI, HI MID, MID, LO MID & LO PCB
Fit the HPF pcb to bracket and front panel. Orange HPF led is the same as previous pcbs with K short (long once bent) leg to K on pcb.
The Yellow and blue leds are more complicated to bend. See below photos.
Make sure the led legs do not touch the switch metalwork or fit plastic tube over the legs.
K legs of leds are always at the front edge of the pcb and can be identified as the leg next to the flat side of the plastic led
Fit jumper shunts on to the preferred cut/boost dB amount per band
Add wire link to bottom of LO PCB (NO longer needed on newer pcb dated 240405)
Fit HPF, LO, LO MID, MID, HI MID, HI PCBs to front panel and bracket and do up nuts
Make up ribbon cable. Red stripe to pin 1 triangle marker on plug.
Hand press these plugs to the ribbon cable one at a time and use a vice to squeeze them fully down.
When testing you can get audio out of EQ with only HPF PCB plugged in.
Any of the HI, HI MID, MID, LO MID & LO band PCBs can be plugged in by themselves or left out for testing.
