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About LarryF

  • Birthday 12/11/1943

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  • Location
    Rio Rancho, New Mexico
  • Interests
    Classical music, fast cars and Maine Coon cats
  • About
    I have been chief janitor at Lectrosonics for 40+ years.
  • Interested in Sound for Picture

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  1. From lunchtime chats with Gordon (Lectro Pres), I understand we have received recent IFBlue shipments that catch us up on most backorders. Further, we are going to receive enough units in the next few days that will allow us to even put units on the shelf. The current global semiconductor supply chain shortages due to fires and Covid are playing Hell with delivery schedules. The positive way to look at it, is that the Black Plague was worse. Best Regards, Larry Fisher
  2. Those are rated in mWh not mAh. Since they are 1.5 Volts that would be 2000 mAh. All that aside, if they give you the times you need, then they are fine. Best, Lef
  3. In today's electronics, switching power supplies at the power input of the transmitter pull a fixed Wattage. Therefore, for a higher input voltage, less current is pulled. That means a lithium battery that maintains a higher output voltage over its life, will run at a lower total current draw, making it run longer. Alkalines start at 1.5 Volts and fall relatively rapidly to end of life at 0.8 Volts. NiMh start at a low 1.2 Volts and stay there until they suddenly die. Lithiums maintain 1.5 volts down to 1.2 Volts for a longer time. The current draw on a lithium is 20% less at the beginning than for a NiMh. Since most of the transmitters are current hogs, the higher current capabilities of a lithium mean the voltage stays higher, resulting in a lower current draw and longer life. Alkalines give up voltage early and result in higher current draws. All of this would be clearer if batteries could be rated in Watts. However, this would fluctuate with the load making things even more confusing. Interestingly, under very light loads such as 100 mA or less, alkalines have more competitve lifetimes since their current is now delivered at a higher, light load voltage. Under very heavy loads such as 4 to 5 amps, Ni-Mh are ideal since their output voltage is constant even at very high loads. For transmitters running middle of the road 5 to 8 hour discharge rates such as 500 mA, lithiums are the choice. Best Regards, Larry Fisher
  4. Hi Donald, My suggestion is as always; eleminate, then test and then add back until you find the guilty party. Try running the Lectros without the distribution device, i.e., the Lecros with just whip antennas. Do everything else the same with the A10's and see if the problem is now cleared up. The repair department has been reporting a number of RF overload and interference problems with distribution amps. If you've done this already, then it may be time to look at the output of the A10's with a quality spectrum analyser. Best Regards, Larry Fisher
  5. It's the middle connector that is the offender. Note the lower arm is going to the outside of the middle output connector which is connected mechanically to the box. There should still be a balun in the circuit. Best Regards, Larry Fisher
  6. L is 1/2 wavelength or 26" at 216 MHz. The individual arms would be about 13". The upper and lower connectors' outside shells are grounded to the case, though this has little to do with operation. The 200k resistor is to discharge static electricity and can be almost any value greater than 1k. What is not shown is a balun to convert the balanced arms of the dipole to the unbalanced shielded cable. Also, the way this is drawn, the case would have to be plastic or the lower arm is shorted to the case by the output connector. Look for an example on the web that uses a folded cable or a ferrite transmission line transformer at the output to form a balun. Best Regards, Larry Fisher
  7. My error in reading too fast. Those lithium AA batteries are even worse about charge detection. The internal LiPo battery in the AA's is running at 3.7 to 3.2 (?) Volts and an internal power supply knocks the voltage down to a regulated 1.5 Volts or thereabout until the internal battery dies. The regulator then shuts down quickly to protect the LiPo. Treat them the same as NiMh; only use the timer in the unit. Best Regards, Larry Fisher
  8. It is absolutely impossible to measure the voltage of a NiMh battery and derive its state of charge. Do as your audio guy suggested; fully charge the NiMh and then use the timer to determine how much time expended and/or left. The power light color is absolutely meaningless for NiMh be it green, red or purple, except to tell you that the transmitter is on. Best Regards, Larry Fisher
  9. Here's a test on some AA rechargeables after a year of use in solar lights, i.e., many charges and discharges. https://www.bing.com/videos/search?q=projectfarm+rechargeable+AA+Batteries&&view=detail&mid=12C4897AB10FFD02F03712C4897AB10FFD02F037&&FORM=VRDGAR&ru=%2Fvideos%2Fsearch%3Fq%3Dprojectfarm%2Brechargeable%2BAA%2BBatteries%26go%3DSearch%26qs%3Dds%26form%3DQBVDMH This projectfarm guy tests a little bit of everything, generally very thoroughly. He doesn't test the Eneloop black, which I found to be the best 5 years ago. But that was 5 years ago. Don't trust the ratings of off brand batteries; the measurements are dreamed up by the marketing depart after being threatend with unemployment if sales don't go up. Best Regards, Larry Fisher
  10. IMHO, I think the 4060 is the better choice. On loud signals, you can use "0" with no transmitter preamp problems. Make sure whoever builds the connector, uses the Lectrosonics recommended 1k resistor. Ignore the DPA recommendation of no resistor on the 4061. Set the gain according to the transmitter manual. Best Regards, Larry Fisher
  11. It sounds as if something in your equipment setup or location is interfering with the RF signal. Take the SRc and the SSM, by themselves, to a different location and see if they then act normally. And by themselves, I mean the SSM with just a lavaliere and the SRc with nothing hooked up to it but power. If you have to have a mixer to listen to the SRc, use a long cable (10 foot+) to get the mixer/recorder away from the SRc. By a different location, I mean a quarter mile away from any camera gear, lighting gear, remote control gear or other electrical devices. If the units work properly in a sanatized environment, you then start adding stuff to find the culprit.
  12. LarryF


    We've shipped about 40 in the 941 band. More units are waiting on parts. Lectro, like a lot of electronic manufacturers, is having to work around irregular parts shipments. Best Regards, Larry Fisher
  13. LarryF


    Sounds right. Those adapter cables I linked above would have taken care of the Beats By Dre (oof indeed). LEF
  14. LarryF


    Since the minijack was also the antenna connector, it had to be isolated, not bolted to, the metal case on the R1a. There was a plastic grommet added but it was still a weak point. The IFBlue case is plastic and the mini can be bolted directly to the case. Better, but it is still a minijack. The minijack is just a weak connector but is the de facto plug type for headphones and ear pieces. Converting to a right angle mini on the headphone cable is a big improvement, since it has much less leverage on the jack and is harder to pull out: https://www.amazon.com/Seadream-3-Pole-Female-Headset-Extension/dp/B01DCBJ51I3 Best Regards, Larry Fisher
  15. LarryF


    Two comments from a very biased fanatic: 1. There is plastic and there is plastic. Gordon told me, that he bent the clip and battery door until it scared him and he quit. However, the replacement parts are cheap enough and easy enough to install, to keep around as spares, even if it is for years. 2. Lectro is a small volume company building many items in quantities of ten to one hundred at a time. The Korean partner (IFBlue) makes items in the thousands at a time and they build for multiple companies. Their costs are proportionaly lower. If Lectro built $500 smart phones in Rio Rancho, they'd be $10,000 even on a fire sale. Best Regards, Larry Fisher
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