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Microdot to Lectro TA5 failure

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Recently on set one of my lavs stopped working and I traced it to the Microdot to Lectro connector (part# is DAD3056). I'm not sure what happened exactly but the threads were pulled right off of the connector. The threads remained inside the Microdot connection but I was able to pull them out with needle nose pliers. You can see in the photo that the tip of the connector on the left is smooth where the threads came off and the intact connector on the right is still threaded. I'm curious if this has happened to anyone else. These babies are $100 bucks a piece so it's a bit of a loss but a necessary item.

 

I noticed there is a knockoff of these adapters made by YPA. Anyone tried one of these?

 

IMG_5109.jpg

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Never had that happen. One of my adapters once broken and I just replaced it. Yes they are pricey, but sending it in and the repair cost and all is just as expensive as simply replacing it. 

 

Whatever you do 

DO NOT buy chinese knockoffs. 

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I 've worked with the YPAs when the old original DPA adaptors were still delivering very hot in gain on the Lectros. DPA changed their configuration some years ago, since then their adapters work smoothly.

YPA has the right config, but the threading on the microdot side of my adapters was poorly made and with actors movements they easily lost connection. Maybe this has been fixed in the meantime, but when the new DPA 3056 came out I switched back to the originals and have not have any failure since then.

 

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This happened to me this week. I was tightening and the microdot on the adaptor just shredded.  I wonder if they got a weak batch.

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I found out that DPA warranties their adapters for two years. I emailed them for an RMA and just sent mine in today. I'll let you know what I hear back.

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Agreed on the hardwired TA5F if you don't need microdot compatibility elsewhere.  We had several 4060's where the microdot end of the cable failed and I repaired them by wiring direct to TA5F.

 

Interestingly, the DAD6012 adapters we used to use were sold specifically for use with the (now ancient) M185 VHF transmitter.  Those (and more recent ones like the DAD6021) connect the shell to pin 1, which on the VHF transmitters shorts out the VHF antenna.  Rewiring direct allows one to change this if desired - although while we still use our VHF transmitters on occasion I highly doubt even we would use a 4060 with them any more.

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I have heard that every time you connect and disconnect a micro dot connector you are loosing contact. The more you plug and unplug, the quicker your contacts wear out. In addition to the microdot assembly being somewhat fragile. 

 

They look cool. 

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On ‎7‎/‎23‎/‎2018 at 10:39 AM, Dalton Patterson said:

I have heard that every time you connect and disconnect a micro dot connector you are loosing contact. The more you plug and unplug, the quicker your contacts wear out. In addition to the microdot assembly being somewhat fragile. 

 

They look cool. 

Hm. Never heard that.

 

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On 7/26/2018 at 10:49 PM, RadoStefanov said:

Never heard that.

Me neither, at the time I heard it. I was skeptical but retained the information. Here is some info I managed to find that explains what I was referring to as "Insertion Loss". I am not 100% this is talking about the same thing. I am referring to the loss of plating on the contact of the physical pin itself decreasing over time and therefore decreasing your RF passing through the SMA connection. I think the accurate description would be copper losses. 

 

-----------------------------------

What is Insertion Loss and how is it specified?

Dec 23, 2014 
 

Insertion Loss, expressed in dB is defined as 10*log (Po/Pi) where Po= Power Out and Pi=Power In. There are 3 main causes of Insertion Loss: Reflected losses, Dielectric losses and Copper losses. Reflected losses are those losses caused by the VSWR of the connector. Dielectric losses are those losses caused by the power dissipated in the dielectric materials (Teflon, rexolite, delrin, etc.). Copper losses are those losses caused by the power dissipated due to the conducting surfaces of the connector. It is a function of the material and plating used.

In general, the insertion loss of a connector is on the order of a few hundredths to a few tenths of a dB. As with VSWR, it can be specified as a “flat line limit” or as a function of frequency. A BNC connector is specified at .2 dB maximum when tested at 3 Ghz. For the SMA, the requirement is .06*SQRRT Frequency in GHz when tested at 6 Ghz. For example, at 4 Ghz, the requirement would be .06*2 or .12 dB max. Although the connectors are specified to operate over a wide frequency range, they are only specified for testing at particular frequency because the test procedure required to obtain accurate measurements of such small losses is a very precise, and time consuming process.

Amphenol RF Link

-----------------------------------

 

For anybody curious, this all started on my end because I used to take my antennas on and off in my wireless case until somebody told me that was a bad idea because you loose .00001db of RF each time. I replied, ohh. ok. Unsure as to the validity of the statement. However after further research. I tend to follow that way of thinking and now keep my antenna's and SMA connectors connected unless necessary to disconnect. 

 

I hope this helps. 

 

Stay cool in that Vegas heat @RadoStefanov!!!

 

Best, 

 

Dalton

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Dalton and Rado,

Increased losses from connecting and disconnecting RF connectors is pretty much a myth. I would get a very tiny magic marker and mark a tiny line on the side of the SMA or BNC connector. After I counted 10,000 lines, I would put on a brand new connector.

Best Regards,

Larry Fisher

 

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IMG_2625.jpg

 

Pick N' Pluck for the win!

 

In conclusion, for all intents  and purposes I will keep the connectors connected. Thank you both for your responses. 

 

15 hours ago, LarryF said:

pretty much a myth

I am unclear. Does the loss exist? However it that the loss is not practical loss ( i.e to be able to be shown on test equipment)? 

 

15 hours ago, LarryF said:

mark a tiny line on the side of the SMA or BNC connector

Are you suggesting I make a new mark every time I connect/disconnect the connector? That will add significant time to my workload over a long period of time keeping track of that process. In addition to physically taking on and off the connectors, I would also have to mark them with a line. I have heard of this process to keep track of the number of uses on components, but feel an alternative approach could be successful ( i.e. keep the antenna's connected at all times). 

 

15 hours ago, LarryF said:

After I counted 10,000 lines

I better have a house and be retired. Haha. 

 

I get the Idea, I am not going to worry about this issue any longer. 

 

I appreciate your time guys!@

 

 

D

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Hi Dalton,

And the terrible thing is, if you forget to mark the lines in the heat of battle, you have to start all over again.

Best

Larry F

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4 hours ago, LarryF said:

Hi Dalton,

And the terrible thing is, if you forget to mark the lines in the heat of battle, you have to start all over again.

Best

Larry F

 

LOTD!

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