Tascam Tech Support says 49 ft is the theoretical max. After that distance your on your own. All extensions require Canari quality cable. There is an 8 page document from Tascam in the DA88 Service Manual folder with complete pinouts.

For the MU8824 Meter Bridge
Canari P/N MR-202-XXAT where XX= 8,16,24 bepending on the # of channels required.
1 ea ;Shielded 15dbM,15dbF per 8 ch.
Cable # pin #s
1 1,7
2 2,12
3 3,14
4 9,13
5 4,10
6 11,15
7 5,6
8 8, tie to shield
solder all shields to connector case, both ends.

For the RC848 Remote/Autolocator
Canari P/N MR-202-4AT
1 ea Shielded 15dbM ,15dbF
Cable # pin #s
1 1,2
2 3,4
3 10,11
4 13,14
solder all shields to connector case, both ends.

For PW88S sync cable
Canari P/N MR-202-8AT
2 Shielded 15dbM
Straight parallel connection EXCEPT PINS 12 AND 13 MUST BE OPEN. Wire pin 11 as a single cable and leave one pr. unused. Solder all shields to connector case, both ends.

Terminator
db15M
Pin Resistor Pin
1 200Ω 2
3 200Ω 4
5 200Ω 6
9 300Ω 10
9 300Ω 12
11 1.5kΩ 12