Cobra 148 Channel kits

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MightyMo
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Cobra 148 Channel kits

Post by MightyMo »

I've been recently looking into channel kits for my 148 (front mic). I've found a handful of kits. I'm just wondering if any of you have ever used one and what you would recommend. I've found several from LessComm (not sure what the differences are beside the price), Digimax, and Expo 100. Digimax and LesComm kits seem significantly more expensive than the expo 100. Not sure why. All this is new to me so any info or experience would be appreciated. If/when I do a kit, I would like, (but not necessary), a scan function. I can't figure out if Digimax has a scan on it or not.

Also, I keep reading things about "The Mod". From what I've gathered it's not so much a kit, as a list of mods. But I can't find a source for it besides just talk about it? Any ideas?

Thanks.
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redlght
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Re: Cobra 148 Channel kits

Post by redlght »

The LC kits are ok but do not show on channel display the digimax converts the 2 digit channel display to 3 digit read out, they are nice but i found in some radios washington cobra 2k 142 ect they produce noise over some channels because the radios are not friendly to digital circuits like the digimax

The expo line of kits are the cheapest because they use mixer crystal switching to generate the new frequencies but are prone to alignment problems from one band to another and from am lsb usb. I used all the kits mentioned plus the old toggle and rotary switch mods i would pick the digimax if a bit of digital noise over a few channels is not a big issue. If the noise is a problem then get a radio that had them built in. If funding is a problem i am sure there are PPL mods in the forums that would suit your needs if not post in the section for mods.

The mod was a kit made by a few guys that never really panned out it is overly complicated and costs as much as the other higher priced ones and IMO not as good.
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Re: Cobra 148 Channel kits

Post by sonoma »

some of the front mic 148 radio's will not take the channel mods used to get extra channels . the L kit has worked fine for me over the years but are next to impossible to find now. some of the newer front mic radios they changed the MB8719 PLL and it will not take the toggle switch extra channels. the expo 100 L kits will give you 40 up and 40 down if you are able to find one. the older 148 radios that will take to PLL mods will give you most of the channels that most CBers use. if you are wanting to at least look at the switch mods for the PLL it is list on cbtricks.com. I will see if I can post a link to it. here is 2 versions of the channel mod using the PLL if yours will take it.the MMB8719 and rci8719 and mb8719-99 I believe are the pll chips that will not take the PLL channel mods. maybe some one else will chime in on the chips that will not take the mods.

http://www.cbtricks.com/membe ... rsion2.gif

http://www.cbtricks.com/membe ... ersion.gif
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MightyMo
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Re: Cobra 148 Channel kits

Post by MightyMo »

Thanks for the responses. I think I'm leaning towards the Digimax. That's good to know about the PLL and the digital noise. I'll look into that. Is there a way to choke out the noise with a filter somewhere in the install?

I've seen the 2 toggle switch channel mod. I was almost planning on doing it when I came across the Digimax. I'm planning on getting a ham license eventually and like the idea of expanded use for my 148. Especially if it has a scan. We'll see. It's all time and money.
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Re: Cobra 148 Channel kits

Post by MDYoungblood »

Now a days there are too many choice's of radio's "Freeband" ready to buy than to mod an older model CB radio. But if you your serious, watch for the Expo "L" kit like sonoma said, best mod for that radio, that was the kit to get before the "Conversion" radios became popular.

3's

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"321, West Manchester Township, PA"

Official Moderator - CBRT Complaint Department
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redlght
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Re: Cobra 148 Channel kits

Post by redlght »

MightyMo wrote:I'll look into that. Is there a way to choke out the noise with a filter somewhere in the install?
I have tried a few different filter types with no luck and the digimax encoder puts noise over channels like 47 and a few others it sounds like a high pitched tone but if channel is active it drowns it out. How ever a cheap filter is two 1n4148 diodes together cathodes opposing each other in the Positive power lead for the mod. How ever i used the mod on washington's and cobra 2k's and 142's never tried it on a 148. Here is a post with the video of my washington in it
http://www.cbradiotalk.com/vi ... 20&t=29657
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MightyMo
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Re: Cobra 148 Channel kits

Post by MightyMo »

redlght wrote:
MightyMo wrote:I'll look into that. Is there a way to choke out the noise with a filter somewhere in the install?
I have tried a few different filter types with no luck and the digimax encoder puts noise over channels like 47 and a few others it sounds like a high pitched tone but if channel is active it drowns it out. How ever a cheap filter is two 1n4148 diodes together cathodes opposing each other in the Positive power lead for the mod. How ever i used the mod on washington's and cobra 2k's and 142's never tried it on a 148. Here is a post with the video of my washington in it
http://www.cbradiotalk.com/vi ... 20&t=29657
Very cool. Thanks. A little bit of noise isn't a big deal. So it looks like it has an auto scan on it. Is that right? Can you program it for instant channels too?

-- Mon Nov 21, 2016 10:26 pm --
redlght wrote:
MightyMo wrote:I'll look into that. Is there a way to choke out the noise with a filter somewhere in the install?
I have tried a few different filter types with no luck and the digimax encoder puts noise over channels like 47 and a few others it sounds like a high pitched tone but if channel is active it drowns it out. How ever a cheap filter is two 1n4148 diodes together cathodes opposing each other in the Positive power lead for the mod. How ever i used the mod on washington's and cobra 2k's and 142's never tried it on a 148. Here is a post with the video of my washington in it
http://www.cbradiotalk.com/vi ... 20&t=29657
Very cool. Thanks. A little bit of noise isn't a big deal. So it looks like it has an auto scan on it. Is that right? Can you program it for instant channels too?
pabxone

Re: Cobra 148 Channel kits / Digimax Lite

Post by pabxone »

The noise you hear on "some" radio's with the Digimax Lite is Multiplexer noise coming from the 3 digit LED display.

I've installed a lot of Digimax's and some radio's are more susceptible to the noise , both Uniden and Cybernet radio's can suffer from it.

The worst offenders are the older Uniden mid size chassis radio's like the Cobra 140 , President McKinley , Stalker IX / Stalker XV , Robyn SB505 , Realistic TRC450 radio's with the PC385 circuit board.

I've tried lots of filtering and choking methods to get rid of the noise with only limited success.

However these filters are the solution :-

https://www.aliexpress.com/it ... f5acc4754b

You feed power to the DigiMax ONLY thru the filter and all the multiplexer noise will be gone.

A cheap quick and easy solution.
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Re: Cobra 148 Channel kits

Post by redlght »

I used those L filters they didn't help, the two diodes in the Pos line did as much good for the washington install
Yes the DM has scan mode works with the squelch you can set one home channel not a bunch of mem channels
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