jawharp Posted October 12 Report Posted October 12 Hey guys, Anyone made a custom cable to go from an MPT60 to a PHA60 for powering a boom? I had a 3 pin lemo and ta5 connector lying around and needed one so I wired one myself using the Wisycom documentation, but it's not working properly. I'm getting really low signal from my 416 and a lot of noise floor. The orientation I used was: LEMO: Pin 1 - Ground Pin 2 - VDC Pin 3 - AF TA5: Pin 1 - Ground (Lemo Pin1) Pin 2 - AF + (connected to Lemo Pin3) Pin 3 - AF - (Shorted to TA5 Pin1 for reference) Pin 4 - VDC (connected to Lemo Pin2) Pin 5 - Additional ground (Tried both shorting to TA5 Pin1, and leaving it open.) Everything tested with a multimeter, no shorts anywhere. All attempts have yielded a big noise floor of hiss with very low boom signal. Tried MPT60 audio mic setting set to "PHA60-48V" as well as "PHA60-12V." No change. The TA3 to XLR cable I've been testing with is just straight 1-1, 2-2, 3-3. Is there more to the Wisycom $100+ cable than just soldering? Is there some kind of circuitry in that cable that I'm not thinking about? I don't understand what I'm doing wrong. Any help appreciated. Thanks Quote
The Documentary Sound Guy Posted October 13 Report Posted October 13 I'm confused. How are you plugging a TA3 cable into a TA5 socket? And why are you wiring Lemo3 to TA5 instead of a straight XLR? Either way, if you have DC power wired to pin4, pin4 doesn't appear to connect to the mic at all. I can't speak for the MTP60 side of the schematic, but phantom normally applies the 48V power to both + and - (i.e. both XLR pins 2 & 3). It's not on its own pin. I'm also not sure why you've jumped negative to ground? I'm not an expert, but I would think that will unbalance the connection and raise your noise floor. Quote
jawharp Posted October 13 Author Report Posted October 13 Hi, Thanks for your interest in my post. No, I am not plugging a ta3 into a ta5 socket as that would be physically impossible. Here are links to the documentation for the hardware i'm referring to: https://fcc.report/FCC-ID/POUMTP60/5561195.pdf https://www.manualslib.com/manual/2626360/Wisycom-Pha60.html There is a phantom power adapter between the mic and transmitter than I am making a cable for. The cable I am making goes from the 3 pin lemo on a wisycom mpt60 transmitter to the ta5 port of the phantom power adapter. It takes the power from the mpt60 transmitter and bumps it up to 48v to power the mic via a 3 pin mini xlr out that goes to a condenser microphone to provide it the phantom power it needs to send audio signal to the transmitter. Thanks Quote
The Documentary Sound Guy Posted October 13 Report Posted October 13 Ah, I didn't realize there was an additional piece of hardware involved. I'm still not clear what signal flow you are using: You've referenced a PHA48, and linked to a manual for a PHA60. Don't think I can be much help, sorry. I don't actually own the gear you are using. Quote
jawharp Posted October 13 Author Report Posted October 13 That's my bad. I originally posted "PHA48" I meant PHA60. It provides 48V to a mic plugged into an MPT60. Quote
Conor Posted October 13 Report Posted October 13 Is yours a PHA60 or a PHA60D? I ran into similar issues recently making a cable for a customer and Wisycom had neglected to provide the correct updated wiring scheme for the newer "D" revision This is the wiring info for the PHA60D: Quote
jawharp Posted October 13 Author Report Posted October 13 Holy shit THANK YOU. Yeah, it's a PHA60D. They really need to make that available to everyone. Glad I didn't fry anything... Thanks! Quote
Conor Posted October 13 Report Posted October 13 Yes, this made a fool of me as well. Glad I could be of help Quote
The Documentary Sound Guy Posted October 14 Report Posted October 14 I don't know what's up with Wisy, but every experience I've had with their documentation, there's been missing or wrong information. I can't help but highlight that even the 'correct' diagram has a mistake (Should be 3V on pin-2 Lemo, definitely NOT 3W). Quote
Conor Posted October 15 Report Posted October 15 16 hours ago, The Documentary Sound Guy said: I don't know what's up with Wisy, but every experience I've had with their documentation, there's been missing or wrong information. I can't help but highlight that even the 'correct' diagram has a mistake (Should be 3V on pin-2 Lemo, definitely NOT 3W). Come on, we both know that's just for "volt" with an Italian accent! Jokes aside - I've always found their documentation information very dense and not very easily accessible. Hardly full of errors though, in my experience. Just takes a lot of head scratching to extract what you're looking for from the available information. The Wisycom User facebook group is a great resource of information from people who have already done the head scratching, but it really shouldn't be relegated to a facebook group. They could really benefit from something like Lectrosonics' "The Wire Lists" Quote
jawharp Posted October 18 Author Report Posted October 18 Okay, I feel like I'm losing my mind now. I wired it according to the updated diagram and now it doesn't even power on the PHA60D, and the transmitter won't boot up while the cable is attached. I did everything in the schematic including connecting the shield to the connector bodies. Is there a chance they changed this again without telling anyone? No results with mic mode set to 48 or 12 volts. Quote
Conor Posted October 21 Report Posted October 21 That's odd, I received confirmation from our customer that the cable is working with the above updated pinout Quote
jawharp Posted October 21 Author Report Posted October 21 crap. maybe i messed something up. i quadruple checked the connections. i didn't have a crimping lemo, but i thought i still got a good connection between the shield/connectors. do you know if an air gap between the shield and connector would cause problems as big as the ones i'm having or would it just make the cable more succeptable to interference? i wound up buying a couple of the wisycom cables cause i need something that works, but i'm kind of bummed i can't make my own with low profile connectors and a shorter length. hope i didnt fry anything! 😐 Quote
Conor Posted October 21 Report Posted October 21 The shield to shell is usually just for RFI rejection as you mention but it is odd that it's then tied to TA5F pins 1 & 5 which is something I've never seen before, with a separate ground on TA5F pin 3 Quote
jawharp Posted October 22 Author Report Posted October 22 yeah, i don't know what they're doing with this cable. i wound up buying one and it works cause i needed something for a job. i emailed wisycom a few days ago, but so far i got no response whatsoever. if they wind up responding i'll post it here Quote
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