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New Palomar Ceramic Microphone

I just whipped up another one. This one really makes the Palomar look bad... I hadn't used the CR-577 in a while...think I'll be going back to using it full time. The meter shows a higher mean as well. Remember that this is actual OTA audio, coming out of a radio, not a mic tester.

 
Hi, this is Eric Lewis with Palomar. We just created an account so that we can hopefully provide another level of customer service at the WWDX forum. It is great to see that the SL41 is getting out there and being talked about. I appreciate it very much! We hope to contribute to the forum and answer any questions that members have. I'll try not to get too wordy!

The SL41 is not a ceramic element, like the CR-577. The SL41 uses a noise cancelling electret condenser element that we had customized for the microphone. It is a true noise cancelling (bi-directional) ECM that is ported on both the front and back of the element. This is why the SL41 grill area extends out from the front case to allow for ambient noise to enter the front and back ECM ports at the same time and effectively cancel each other out.

The pro's to our noise cancelling ECM are sound quality and gain. Using an ECM we are able to have a much wider frequency response and sensitivity than dynamic mics. This means that on some radios you might need to turn your mic gain down, but even with your mic gain turned down I think you will get very favorable audio reports on air.

The con is that it does require a battery to universally work with any radio. However, my engineer designed the mic with battery conservation in mind and we estimate that a standard alkaline AAA battery will last 2 years under normal operating conditions. The battery is only there to energize the ECM during TX. Also, we used the most common battery we could fit in the mic - knowing that eventually the battery will need to be replaced.

We spared no expense in creating the SL41 and I think this will be obvious to people when the hold the mic in their hand. It is very sturdy and we made it to last. The SL41 was designed by the same engineer that designed the AR-3500 (for those that remember the Clear Channel days) - I am very excited to be working with him again. We are going to make some great products!

To end with a bit of 'insider info' - yes, I named the microphone for my dad. SL for Sam Lewis and 41 for the year he was born. The SL41 is the last product that he and I developed together before he passed away last year. Through a minor legal battle, I was able to regain the rights to the Palomar name a couple of years prior and it was our plan to launch this mic under the revived Palomar brand. It is my intention to make Palomar what is was when my grandfather and dad ran it.

Thanks and sorry for the ridiculously long post! As I mentioned, I'm new at this.
Thanks Eric
I'm still running my Skipper 300, how about a remake?
 
You could always build your own for a fraction of the price.
It's a great sounding microphone built with cheap Chinese parts designed to physically resemble a Shure 577b.

Here is one I put together with an electret that had the same specs as the Palomar SL41.
DSCN5857_zpsgz0fbddg.jpg

DSCN5852_zpsvgyzguze.jpg

DSCN5860_zpsjrn8thtu.jpg


For the electret just get
Mouser Part #: 665-ANM-5254L-R and you're halfway there.
Screenshot_2017-03-30_17-30-26_zpsoqlbbgto.png

50hz-16000hz. Awesome response and noise cancelling as well, assuming it is put into a case with a rear sound entry port like this one.


Meanwhile, here is the Palomar over the air..
 
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Won't get the noise-cancelling feature mounted that way.

The tiny hole in the rear of the capsule is for ambient noises to enter the rear of the electret capsule. To make it a noise-canceller, the capsule would need to be just under the screen, out in front of the housing with the rear of the capsule exposed to surrounding noises.

Probably works okay the way you see it, but that's how a noise-cancelling element works. Sound that's louder in front than it is in the rear of the element gets heard. Sound coming from a distance is equally loud in the front and rear. Cancels it out.

73
 
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Won't get the noise-cancelling feature mounted that way.

The tiny hole in the rear of the capsule is for ambient noises to enter the rear of the electret capsule. To make it a noise-canceller, the capsule would need to be just under the screen, out in front of the housing with the rear of the capsule exposed to surrounding noises.

Probably works okay the way you see it, but that's how a noise-cancelling element works. Sound that's louder in front than it is in the rear of the element gets heard. Sound coming from a distance is equally loud in the front and rear. Cancels it out.

73
that's precisely why I used the Electro Voice 603t housing for mine.
There is an opening on the back of the case directly over the electret which allows the background noise to enter the back of the electret to cancel itself out. It would be nice if somebody would mass-produce something similar.
DSCN5852_zpsvgyzguze.jpg
 
Somewhere in my closet of goodies I have a Palomar SSB-500. It needs work and someday I may fix it.
I have a Palomar 500SSB as well. Sweet radio. Mine is NOS/Store Demo unit. My relay sticks some times but I have a NOS spare relay. In the fast I put a drop of 100% silicone lube on it. I picked a NOS audio IC and a few other parts for it that popped up on ebay a few years back. Everyone thathears it wants to buy it off me. It is gigantic chasis though for a mobile and it has more electrolytic caps than President Carter has liver pills!!!
 
that's precisely why I used the Electro Voice 603t housing for mine.
There is an opening on the back of the case directly over the electret which allows the background noise to enter the back of the electret to cancel itself out. It would be nice if somebody would mass-produce something similar.
DSCN5852_zpsvgyzguze.jpg
I am using an Electrovoice as well but mine is a 600EL that has a dynamic element in it. I am replacing it with a Gentex Electret that is armored against EMI/RFI, water resistant, almost flat response 50hz-16Mhz. The one I am using is not noise canceling but it has a very narrow pattern so that any noise off axis is attenuated a lot! Gentex makes a lot of elements for Aviation and Military. The ones I am using are built just like their Aviation style but where biased towards call center headset's so they clatter of the keyboard and the other agents and such is not picked up. You guys know that if you need more gain from your mic for a low gain radio audio circuit you can wire another electret mic element in parallel for 40% increase in gain over running a single element. I have never seen much benefit from passive noise cancellation in a hand mic in terms of either the element/cartridge itself or dual phasing elements in a hand mic. I have DC, Bose,Telex,Flight-Com and many other aviation head sets going back to flight school in 1993 and never been too impressed with passive attenuation. The active systems all work fantastic but they are all expensive too. I also have a NOS Mura dual phased noise canceling hand mic and it is a great mic but the "noise cancellation" feature is nothing great! If anything passive filtering of those freq's you do not want to pass is prob. the most reliable but it always degrades the voice as well. People always choose the wrong radio/mic/mod combo for the vechile and environment they plan to operate in. A radio and it's mic and all the other mod's or black box's all have to be playing from the same song book. You do not put a butchered hacked up Galaxy with a Power Mic into a hot-rod, 4x4 with load exhaust and big tires or a tractor trailer!!!! You can not just take mod's and mic's and toss them at a radio and see what sticks! I have never seen a noise canceling mic really solve a problem. A power mic does not fix a poorly adjusted or poorly tuned radio. A noise canceling mic does not solve the problem of a butchered radio in a crappy environment!
 
I am using an Electrovoice as well but mine is a 600EL that has a dynamic element in it. I am replacing it with a Gentex Electret that is armored against EMI/RFI, water resistant, almost flat response 50hz-16Mhz. The one I am using is not noise canceling but it has a very narrow pattern so that any noise off axis is attenuated a lot! Gentex makes a lot of elements for Aviation and Military. The ones I am using are built just like their Aviation style but where biased towards call center headset's so they clatter of the keyboard and the other agents and such is not picked up. You guys know that if you need more gain from your mic for a low gain radio audio circuit you can wire another electret mic element in parallel for 40% increase in gain over running a single element. I have never seen much benefit from passive noise cancellation in a hand mic in terms of either the element/cartridge itself or dual phasing elements in a hand mic. I have DC, Bose,Telex,Flight-Com and many other aviation head sets going back to flight school in 1993 and never been too impressed with passive attenuation. The active systems all work fantastic but they are all expensive too. I also have a NOS Mura dual phased noise canceling hand mic and it is a great mic but the "noise cancellation" feature is nothing great! If anything passive filtering of those freq's you do not want to pass is prob. the most reliable but it always degrades the voice as well. People always choose the wrong radio/mic/mod combo for the vechile and environment they plan to operate in. A radio and it's mic and all the other mod's or black box's all have to be playing from the same song book. You do not put a butchered hacked up Galaxy with a Power Mic into a hot-rod, 4x4 with load exhaust and big tires or a tractor trailer!!!! You can not just take mod's and mic's and toss them at a radio and see what sticks! I have never seen a noise canceling mic really solve a problem. A power mic does not fix a poorly adjusted or poorly tuned radio. A noise canceling mic does not solve the problem of a butchered radio in a crappy environment!
The passive noise cancellation works great on this one plus a .1uf capacitor acting as a high pass filter helps as well
DSCN5715_zpshwqrarth.jpg
 

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