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I install antennas in areas where I have verified that 600MHz LTE signals are now present. I've been using Linear LPF-600s (the only >600MHz filters I could find) and they seem to work fine. However, I went to order more, found they were out of stock all over and the one place I ordered from e-mailed me back and told me they were on backorder with Linear until November. I checked Tin Lee and their filters start at $150. Any other options?
 

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I install antennas in areas where I have verified that 600MHz LTE signals are now present. I've been using Linear LPF-600s (the only >600MHz filters I could find) and they seem to work fine. However, I went to order more, found they were out of stock all over and the one place I ordered from e-mailed me back and told me they were on backorder with Linear until November. I checked Tin Lee and their filters start at $150. Any other options?
Hopefully Channel Master will redesign their LTE filter due to new repack cellular frequency 600MHz.
 

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Since 600Mhz filters can significantly atrenuate channels 35 and 36, a better solution needs to be marketed.
My market has a channel 36 station that is revoved with a 600Mhz low pass so the Channel Master is still the best solution here.
And my service monitor sees nothing in the 600Mhz
spectrum strong enough to cause any issue.
 

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I checked Tin Lee and their filters start at $150. Any other options?
There was a company East of Syracuse NY (Communications & Engineering) but they unfortunately went out of business. They were partners (of sorts) with Tin Lee, but their traps & filters were less expensive.
It's too bad they still aren't around, they were my go-to source from single channel traps. :(
 

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Any idea on shipping??

That $50 notch trap bandwidth is way too wide. 25megs doesn't cut it with even a one channel removed adjacent channel. And that's at -5db down instead of the typical -3db.
 

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Shipping is included in their price and many of Jan Jenca products are about 40 dollars. My last two orders from them took 9 and 12 days from ordering to delivery.
John
 

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I see that now.
 

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Any idea on shipping??

That $50 notch trap bandwidth is way too wide. 25megs doesn't cut it with even a one channel removed adjacent channel. And that's at -5db down instead of the typical -3db.
You'd have to contact them and see if they can make what you want to your specification. They customized a band pass filter for me for $5 above the list price on eBay.
 

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I already have. The time difference kinda slows things down somewhat.
 

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Shipping is included in their price and many of Jan Jenca products are about 40 dollars. My last two orders from them took 9 and 12 days from ordering to delivery.
John
My Jan Jenca order took about 8 days. The bottleneck is customs in NYC, my package stayed there 4 days before it moved on.
 

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Since 600Mhz filters can significantly atrenuate channels 35 and 36, a better solution needs to be marketed.
My market has a channel 36 station that is revoved with a 600Mhz low pass so the Channel Master is still the best solution here.
And my service monitor sees nothing in the 600Mhz
spectrum strong enough to cause any issue.
Jan Jenca made my filter 470-608Mhz. It passes Channel 36 fine, I have a very strong RF36(WUNE). Hope Channel Master is making something similar at a good price point.




 

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The need for this may be growing. T-Mobile lit up a cell tower near my home at 11 AM today, and RF 39 and 40 jumped to a signal strength of nearly 100 on my HDHR, same as the full-power stations on RF 29-36.

It's not causing me any grief, but I wonder about others who may have weaker stations at RF 36 and are also very near 600 MHz-band cell towers.
 

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The need for this may be growing. T-Mobile lit up a cell tower near my home at 11 AM today, and RF 39 and 40 jumped to a signal strength of nearly 100 on my HDHR, same as the full-power stations on RF 29-36.

It's not causing me any grief, but I wonder about others who may have weaker stations at RF 36 and are also very near 600 MHz-band cell towers.

The HDHR shows 100% Signal Strength at 0 dBmV or -48.75 dBm and greater. The TV dynamic range runs up to around -8 dBm or 40 dB stronger. It's too bad they chose to set 100% to 0 dBmV because it's not helpful in seeing how strong a signal really is. In many cases 100% on the HDHR is no problem at all for the TV tuner.
 

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Yeah I kind of figured: even with all my strongest stations at 100, I could still increase amplification quite a bit before I saw any signs of overload. So the HDHR doesn't really tell you how close you are to the point of overload. The best I could do was set my amplification so that a few strong stations were slightly under 100, and as long as the weaker stations were still OK I figured I was fine.

I just don't recall ever seeing a cell tower signal that strong before, and I figure some folks are even closer to a tower than I am, so they might have a problem (especially if they're in a fringe TV reception area).

Strangely, that strong cell tower signal was on for just about exactly 24 hours, then today it switched off again. So it must have been a test. But I suppose eventually it will switch back on permanently.
 

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Any updates on this? I have a tuner that's getting blasted by B71 now in the Seattle area and the 700MHz version is no longer good enough.

I checked CM's website and the CM-3201 now shows 600-2000 as the band-stop. But that might not be good for 36 (or even 35) if they are being literal about 600.

Does anyone have the (apparently) new version? I have ordered it with a note to confirm it's been changed. CM should surely know not to heavily filter 36... right? And Seattle has an RF36. So does LA down here at my primary QTH, but B71 is pitiful where I live in OC rn, so it's not a problem, yet...

The trouble is B71's DL's are right next to RF 37 and the uploads are next to where B12's are. It would be a lot easier for us to filter it, if it was the other way around (as uplink signals aren't constant like downlink).

Thanks,
 

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I received this response from CM just now. I think it's a bit off... but I ordered the CM3201 and will test it on 35 and 36 here to see how much it degrades those two here before I take it to WA:

Mike,

I spoke with engineering further on your request here and I do apologize I was incorrect. The LTE filter you purchased [CM-3201] beings rolling off at 609Mhz and will include up to channel 36. It will block the entire T-mobile spectrum and the start of the B71 band at greater than 40db down. I hope that helps you further, if you have additional questions please let us know!

Ann
Customer Experience Manager
[email protected]
 

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This is part of the Engineering spec sheet that CM support emailed to me:



I measured the attenuation of the new CM-3201. The insertion loss for 36 is about 3.3 dB for my sample:

 

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I have a Kliztech amp that has the outdoor covering and the Channel Master LTE filter is too wide to fit the F connector . The input connector is too close to the side wall of the cover . Probably a silly question but will the Channel Master filter out cell signals if I reverse connect it directly to my antenna then have the the RG cable run down to the pre amp ?
 
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