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rf filter

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cmcaldas
rf filter

I'm working on a project and I want to block 5Mhz through 200Mhz so I can insert a new carrier. I've emailed a few companies and asked on-line, but so far... no luck..
I know it's not a regular filter that blocks the return, but if it works right.. could be a good size order. Any thoughts?

thank you in advance

~Carlos

northcoast
Have you tried Eagle Comtronics?

What it sounds like you are looking for is a highpass filter. You will have to remember that a filter has a curve, so frequencies just above the stop frequency range will also be affected. For example an ECHP 216/200 highpass filter will give you 50db of attenuation from 0-200mhz, but your first useful frequency will be 216mhz. Hope this helps.

schg
This German companyhttps:/

This German company
https://www.rittmann-hf-technik.de/
is able to build custom filters for any need at reasonable cost.

cmcaldas
web site

Hi Schg
The link for english doesn't work and I can't find a contact us email address. I hate to trouble you, but would you know what the email address is?

Thank you in advance
Carlos

cmcaldas
Thank you both

I'll see what's currently available from both as well as ability to order a few hundred to start

Thanks again

windwaterwaves
Ingress filters are 5-50 and

Ingress filters are 5-50 and they are cheap you can get them by the truckload, then you can just get another to go from 50-200 that one I would call eagle.

northcoast
filter falloff at edge frequencies

Whatever filters you end up selecting, be sure to provide yourself enough cushion around the edge of the filter that you are not affecting your desired passthrough frequencies. No filter can give you sufficient attenuation and falloff immediately. Best to start with what you want to do and select a filter on that basis. If you need 200 MHz and up to pass cleanly, plan for a filter that blocks 5-180. If you need the full spectrum to 200mhz for something, plan to leave a few channels above that. At the risk of being another old rf guy, the reason that there is a custom filter to 200 MHz is that with a north American channel plan you are passing analog cable 23 and up (superband) while trapping out midband and highband (vhf 7-13). This was useful when sending analog cable from one market to another (via microwave or analog fiber) where you would reinsert local programming and premium channels. I would be very comfortable that that filter works exactly as described because they have been in production for decades.

cmcaldas
Eagle

Thank you everyone
I've attached an example of a capture for one filter I've looked at. it's not docsis 3.1 but uses qams like 2048 to deliver 1Gb in large condo or apartment buildings. thought was to still pass some video services if needed. but like most, streaming will be replacing current video services. I've been doing this way too long lol, I remember when ppv was done by calling the office

thanks again
Carlos

File attachments: 
mtntrailseeker
Microwave filter company in

Microwave filter company in NY. Used them in the past for dropping RF channels and inserting new ones.

cmcaldas
filters

Thanks Tom