sonic_reducer Posted March 3, 2008 Report Share Posted March 3, 2008 Ok, I encountered a strange situation with the pd-6 on set a while back. Its been nagging at me. If anyone knows what the real explanation for this phenomena is, let me know. Was working as a utility a little bit ago, and on my boss's cart, he was running a pd-6 on the 12v pin of a powermax rigged with a 33ah battery, a dv824 with a juicer, and a lectro venue rack. When we switched to bias-T power for amplified antennae, the draw became a bit much, and we noticed the battery consumption was sucking. We stuck to ac power as much as possible that day. That evening, while on AC power, the pd-6 began getting some seriously funky noise (not like a 60hz mess, more of a whishy sound, with a digital artifacty background), and the lectro began turning on and off rapidly the second the pd6 went into record mode. Very scary. The cart began to blink lights like a slot machine. The DV824 was rock solid. (I did check, the funky noise was internal to the pd-6, was going to the track AND the headphones, and was not coming off the mixer or the wireless) We pulled ac power immediately, no dice. It wasnt bad power. I decided that the quick and dirty solution was to run the pd-6 with NP-1's. What i noticed, however was with the PD6 still on external power, the second i put a fresh NP in, the noise went away, and the Lectros worked just fine. Afterwards when I checked, we found that both were getting appropriate voltage (presumably the amperage wasnt so good). Interestingly, for some strange reason, the pd-6 was happy that way in the short term, with a fresh np-1 in, and it switched to external power. When i soldered up a new power cable for the pd6 to keep it on 14v, It stayed happy with no np, and the problem never reared its ugly head again. So, in retrospect, 1. amperage shouldnt have been a problem. Everything was hooked up to AC power. 2. But what about voltage? At 12v, we were getting the noise, but when i put a 14v np, everything was ok.... so... I can only conclude that A. the pd6 is NOT happy at 12 v, more like 14 or so B. The INT/EXT switch for pd6 power is not a discrete switch. Somethow, even on external power, the pd6 pulls voltage from the internal battery, presumably so that when you do switch, you dont lose timecode or ram, menu settings, etc. So perhaps as a safety precaution, one should always have a fresh brick loaded into the pd-6, regardless of the external power. C. There's something about the Lectro venue rack when supplying bias t power that the system i described above doesnt like. anyone want to confirm/deny my suspicions? If i'm speaking nonsense, or have come to an idiotic conclusion, i'd love to know. I'm building my own cart now, and would like to avoid the above scenario. Quote Link to comment Share on other sites More sharing options...
Alan Posted March 3, 2008 Report Share Posted March 3, 2008 1. amperage shouldnt have been a problem. Everything was hooked up to AC power. 2. But what about voltage? At 12v, we were getting the noise, but when i put a 14v np, everything was ok.... so... I can only conclude that A. the pd6 is NOT happy at 12 v, more like 14 or so B. The INT/EXT switch for pd6 power is not a discrete switch. Somethow, even on external power, the pd6 pulls voltage from the internal battery, presumably so that when you do switch, you dont lose timecode or ram, menu settings, etc. So perhaps as a safety precaution, one should always have a fresh brick loaded into the pd-6, regardless of the external power. C. There's something about the Lectro venue rack when supplying bias t power that the system i described above doesnt like. anyone want to confirm/deny my suspicions? If i'm speaking nonsense, or have come to an idiotic conclusion, i'd love to know. I'm building my own cart now, and would like to avoid the above scenario. Firstly how do u distribute your AC power to DC for your DC powered device? Do you have something like the IDX AC/DC adaptor or the Fostex AC/DC adaptor? The PD 6 needs a juicer just like the DV824. 12V battery will not power the PD 6 to specs, unless you are talking about a 12V AC/DC adaptor with at least 2amp current. PD6 sucks 12V like nothing. You are right in keeping a brick in your PD6 at all time. My Venue acts funny only when my SLA battery is low, i will get dim LCD display with motor boating sound. Still its better to run the Venue with another Juicer if you are on battery power. With T-bias on, it draws more power thats why I have UFM50 with me all the time, for the just in case moment. In all, your boss cart need at least 3 juicer when running with SLA battery, and 33AH is not enough. I use to have almost an identical setup with your boss, and I lug around an 80AH battery. With the 3 devices you have, I think you are drawing at least 5 amp, 33AH will run out in less then 6 hours in theory, practically i think 4 plus hours. With juicers its even worst. The first device to act up will be the PD6, if i'm not wrong. If I'm on AC, it will be either the device original power supply or IDX AC/DC adaptor. Beware of juicer plugging into the IDX, I'd done that once and it blew my IDX. Alan Quote Link to comment Share on other sites More sharing options...
sonic_reducer Posted March 3, 2008 Author Report Share Posted March 3, 2008 Thanks Alan, The PSC Powermax was doing all the ac-dc conversion. A Quote Link to comment Share on other sites More sharing options...
Alan Posted March 3, 2008 Report Share Posted March 3, 2008 Thanks Alan, The PSC Powermax was doing all the ac-dc conversion. A Powermax, like on the other thread ( which is your boss, i think ) I think you need to rewire your 4 pin for higher voltage, or throw in another Juicer for your PD6 and Venue. That will be on the safe side if your are using SLA battery with standard 12V power max wiring but however if on AC thru the power max, you can rewire your 4 pin to higher voltage. Even thou you have wire all 4 pin with higher voltage, running on 33AH still does not give you enough run time, unless you don't mind changing batt 3 times in a 12 hour day. My current cart runs on 2 x Li-on V mount battery with PD606 for a 16 hours day, with my Venue on a 160 WH V Batt and the mixer, IEM, Mini-me, SD HX3 and LCD monitor with another 160WH V batt. I got sick of SLA battery. I go home charge my 4 battery and sleep better. Alan Quote Link to comment Share on other sites More sharing options...
Guest afewmoreyears Posted March 3, 2008 Report Share Posted March 3, 2008 Heres one for ya.... sorry for not answering your question, I think others have posted a few good clues... But since were on the topic... My PD6 works great on the Deep cycle marine battery by the way, WITH the EX12.... I am AC all the time for everything on my cart..... Even my radios..... Always have been... Never any problems..... I run the biggest UPC backup/ power dist. unit i can find and let the units rip..... If there is a kick out, the upc kicks in with no power loss.... and if I need power and none is around... (almost never) I fire up the Honda 1000 generator.... Again, I have been doing things like this for a long time and for me it works great..... What can I say.... IMHO....All the battery stuff is more of an accident waiting to happen then the AC... I can go battery 10 different ways if need be, then I go to a Deep cycle Marine battery or a pelican or belt 12v, but 95% of the time AC. Quote Link to comment Share on other sites More sharing options...
Jeff Wexler Posted March 4, 2008 Report Share Posted March 4, 2008 I am AC all the time for everything on my cart..... Even my radios..... Always have been... Never any problems..... I run the biggest UPC backup/ power dist. unit i can find and let the units rip..... If there is a kick out, the upc kicks in with no power loss.... and if I need power and none is around... (almost never) I fire up the Honda 1000 generator.... Again, I have been doing things like this for a long time and for me it works great..... What can I say.... IMHO....All the battery stuff is more of an accident waiting to happen then the AC... I can go battery 10 different ways if need be, then I go to a Deep cycle Marine battery or a pelican or belt 12v, but 95% of the time AC. This surprises me since AC has ALWAYS had way more issues for me --- this is why I have gone with the cart power system that I use now (and have used for the last 10 years or so). Since almost all the equipment is DC powered (in my case) how can powering off a battery supply be "an accident waiting to happen"? As soon as you make the decision to introduce AC in any fashion, you are talking about putting some other device in the chain (to convert AC to DC at the very least). It has been my experience that if you use to so-called AC adaptor that comes with each piece of equipment, this is truly a recipe for disaster. If, on the other hand, you do use a centralized DC source (that may be AC powered) this will help eliminate many potential problems. I guess whatever works for you works for you. I just have had a lot better results and far fewer issues sticking with as little involvement with AC, UPS systems, inverters, converters and such. The less you have to do with AC the better in my book since there are so many other AC issues on the set now with devices that require AC (video assist, Technocrane, etc.) with which we must interface, the potential (pun intended) for ground loops, unpredictable ground potentials and so forth, I like to avoid all of that. - Jeff Wexler Quote Link to comment Share on other sites More sharing options...
Guest afewmoreyears Posted March 4, 2008 Report Share Posted March 4, 2008 Jeff, Agreed, Common sense would say so... but it's worked great...... Again, if I need to switch something out, I can do it in a moment, but so far, never an issue.... I used to run all the good stuff from a large block battery..... but the AC thing seems to be great and I never have to charge it back up.... That I really like.... Very rairly do I get any noise from VTR..... If were in the same power, we seem to be fine..... Quote Link to comment Share on other sites More sharing options...
DustinJones Posted March 4, 2008 Report Share Posted March 4, 2008 Hello, I work for Lectrosonics. There is a known issue with early production Venue Receivers (as Alan has described) where they sometimes become unhappy under full load when supplied by low voltages (under 12VDC). The main switching power supply in the device becomes unstable, causing erratic switching frequency, sometimes even audible as a high-pitched whine. We do have an update to remedy the situation free of charge, but it requires that the unit to be sent back to the factory. To see if your unit was one of the early ones, please contact Lectrosonics service department via our website: www.lectrosonics.com with your Venue's serial number. sonic_reducer, I sent you a PM, though there is no message in my outbox, perhaps it just hasn't been processed yet. If you dont get it, please check my profile and email me. Dustin Quote Link to comment Share on other sites More sharing options...
sonic_reducer Posted March 4, 2008 Author Report Share Posted March 4, 2008 Thanks, Dustin. I forwarded this thread to the mixer in question. hopefully, he will get in touch with you. A Quote Link to comment Share on other sites More sharing options...
Glen Trew Posted March 4, 2008 Report Share Posted March 4, 2008 ...I can only conclude that A. the pd6 is NOT happy at 12 v, more like 14 or so B. The INT/EXT switch for pd6 power is not a discrete switch. Somethow, even on external power, the pd6 pulls voltage from the internal battery... I want to emphasize here that a PD-6 will run correctly with 12 volts. It should not need a Juicer (regulated power cable) unless the external power (such as from a draining battery) drops much below 12V or ground isolation is needed. I think the problem is voltage drop in the cable or connectors. Problems like this could seem to go away by increasing the voltage, but the proper fix is definately to reduce the amount of voltage drop between the source and the machine. There is the outside chance that the problem is due to a faulty internal DC-DC converter, but this is so unlikely that it would be best to rule out voltage drop before looking elsewhere. Glen Trew Quote Link to comment Share on other sites More sharing options...
RPSharman Posted March 4, 2008 Report Share Posted March 4, 2008 Make sure that you are not overloading the individual outputs of the PSC equipment. The Cart Power, Powerstation, Powermax, were not designed to handle powering an individual piece of equipment with significant power draw, or multiple pieces of equipment from only one output. A PD-6 should be fine if fed properly from a single output. When I had my DV824, it ran well on the Cart Power from and AC or DC source. My 33aH was in very good condition and always well charged. The PSC gear have some sort of slow-blowing fuse on the outputs to protect them, so if there is overload, you may experience this phenomena. It will correct itself when you switch to another power source. Power to my gear was my very first priority, having worked for other mixers with somewhat funky setups, or setups heavily reliant on AC power. It is critical to use quality cables of short lengths, and don't get creative with the routing. Robert Quote Link to comment Share on other sites More sharing options...
soundtrane Posted March 4, 2008 Report Share Posted March 4, 2008 I just have had a lot better results and far fewer issues sticking with as little involvement with AC, UPS systems, inverters, converters and such. The less you have to do with AC the better in my book since there are so many other AC issues on the set now with devices that require AC (video assist, Technocrane, etc.) with which we must interface, the potential (pun intended) for ground loops, unpredictable ground potentials and so forth, I like to avoid all of that. I would second Jeff on this. Unless one has something like a dedicated DC source that only takes charging from an external AC source, like the Powerstation... I remember working with mixer Pawel Wdowczak who had two Powerstations on his PSC cart, I would plug into AC wherever available. We NEVER ran out of power. On that cart was an 824, Nagra V, Sonosax mixer, RK4 rack with 4 x 2020 Rx, 1 x 2040 Rx, comtek base station. In fact his Powerstations were kind of old, and at least one of them did not have a decent enough internal SLA battery. I would avoid AC powering of any kind to my cart, unless it is only to charge or trickle charge an SLA battery that would be powering my setup through a distribution system. In my current setup, Cantar powers itself for 16 hours, Lectro Six pack powers itself for 16 hours, One 18Ah pelican battery designed by me powers a Sennheiser 300 Tx, a Datavideo 7" monitor and an iPower 9V charger through a PSC Cartpower. I intend to add a second IFB channel and more wireless Tx in the Sixpack. Even then, I dont think I will need anything more than one more 18Ah battery. best -vin Quote Link to comment Share on other sites More sharing options...
soundtrane Posted March 4, 2008 Report Share Posted March 4, 2008 My current cart runs on 2 x Li-on V mount battery with PD606 for a 16 hours day, with my Venue on a 160 WH V Batt and the mixer, IEM, Mini-me, SD HX3 and LCD monitor with another 160WH V batt. I got sick of SLA battery. I go home charge my 4 battery and sleep better. Much lighter cart as well now? Yippee! best -vin Quote Link to comment Share on other sites More sharing options...
Guest afewmoreyears Posted March 4, 2008 Report Share Posted March 4, 2008 My problem with the whole battery thing is charging them..... I don't have the time or the ability much of the time to do so.... I am always in different places each night and seldom work from my home.... I go out for days on end, away from the comfort of home..... This is the main battery issue for me.... Again, The AC has worked great for years with absolutely NO issues whatsoever.... What can I tell you guys, I know it is unorthodox... but man, it works great.... Quote Link to comment Share on other sites More sharing options...
Philip Perkins Posted March 5, 2008 Report Share Posted March 5, 2008 For clarification: you guys running DC distro on your carts--you hook up to AC when you can, and are using various means to turn it into DC for your gear right? So theoretically the gear is on DC all the time, the only question is whether or not you are making that DC from an AC power supply or from a battery? I try to run on AC (with a "Cart Power" power supply) as much as I can. As the batteries get bigger (looking into that Optima mentioned above) the less I have to handle them and charge them the happier I am. (On my jobs my cart usually goes home with me at night, so charging is my problem--not like a big show where the sound gear is on a well-organized truck etc that is charging lots of gear.) Philip Perkins Quote Link to comment Share on other sites More sharing options...
soundtrane Posted March 5, 2008 Report Share Posted March 5, 2008 I get my cart home every day after wrap. Not a big deal considering the size and weight, it takes us about 10-15 minutes to wrap up. I charge the following every day 1. Cantar Li-Ion battery x 1 (because the machine runs an entire day on one battery, I charge only this one while the other battery remain on the cantar, which gets used the next day, therefore i use & charge each battery every alternate day) 2. Lectro sixpack (with charger provided by Lectro) 3. 18Ah Pelican battery with a smart SLA charger This takes me a total of 2 minutes - to put to charge, and less than a minute to take off the next morning. To answer Phil, yes, the Cart power has an AC in, but I have not used it so far, never needed to. best -vin Quote Link to comment Share on other sites More sharing options...
Izen Ears Posted March 7, 2008 Report Share Posted March 7, 2008 Ha ha I'm not the boss mentioned earlier, I've had no issues with wacky noises or the PD6 freaking out. I'm just like AFY: I've got a Powermax and a Pelican 33ah lead acid batt, and I always plug in all the time. Now after reading about some nightmare situations where a spike from a genny killed a mixer's entire cart, I got a $160 Zero Surge 2R15W surge protector. I did once have a genny kill my Powermax (before I got the Zero Surge) and it had to be sent back to PSC - fried some capacitor or something. Very scary! Also any 60-cycle crapola that screws up the video hard line is mitigated by cubing off the VTR cart, and and hum by adding a ground lift (almost never have to do that though). It's great because I've got tons of stuff powered off the Powermax (PD6/EX12, 6 Lectros [via BDS box w/ 4-pin connector], PSC antenna splitter, Cooper board, monitor), but I can still get by for 8 or 12 hours (haven't had to test it with this config) before needing to plug in, so when I get to set I can afford to use batt power until the juicers run their lines to the VTR cart. Plus I've got a second Pelican batt on the truck just in case. It's great too because those electrics will often power down without telling me but it never disrupts anything. I decided to always charge batts and archive while on the clock, I spend enough time of the day working! I can't conceive of the hassle of working a job where I had to take the cart home and charge batts every night. Damn! Dan Izen Quote Link to comment Share on other sites More sharing options...
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