BCD396XT/BCD996XT: Bring your 3/996XT into the 21st century :)

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pro106import

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If yours don't show up I can part with one. I only need 4 and would like to keep one "just in case", so I'll have a spare.

Thanks Kevin for the offer- I'm sure it will arrive today :D
I will have some spares also. Most of my radios have dual filters already. I took them all apart to check. So maybe, if the forum moderator doesn't mind, we can use this thread as a filter swap fest when the time comes. Or we can start a new thread to share our extras.
Happy Mothers day everyone.
Bob
 

sodjan

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The last sets with the muRata filters shipped earlier today.
I know have 1 last set of *5* filters left. I'll keep them for a while
(if there should be any delevery problem with the kits) as
replacements.

Please remember to leave feedback in eBay when they arrive.
I use my eBay list of "sold items" to monitor the deliveries.

Regards,
Jan-Erik.
 

awattam

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Like most people..

I left it too late to place an order for one of those filters. Has anyone got a spare one to sell and if so, how much would you like for it?

Please PM me..thanks
 

Boatanchor

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GRE/RS scanners

Hello everyone,
I have a Pro-18 scanner, if I replace the murata 50E filter with a 50G filter will this improve my P-25 reception? Conventional p-25 is alright, but some simulcast trunk systems are garbled and that is where I am looking for improvement.

Thanks

Sorry, can't give you a definitive answer on that one. You would just have to try it (with the following caveats in mind).

Firstly, the GRE and RS branded radios use a 455Khz filter, not a 450Khz filter, so the filter specified in this thread is not compatible.

I would be a little surprised if the PRO-18 and the PSR-800 only have one 3rd IF filter.
The previous GRE models (PSR-500 and PRO-106), both have FM and FMN 455Khz filters, so it would be a backwards step for GRE to go back to a single filter in the latest models.

Can anyone out there take a photo of the Homepatrol/HP-1 discriminator section showing the 450Khz IF filter/s?

It would be interesting to see what filtering is in the Uniden HP-1 too..

Rick
 

Boatanchor

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Here you go . HP-1 standard filter

Thanks tumegpc,

Ask and ye shall receive :)
Same single IF filter configuration as the x96XT's..

Now, who's going to be game enough to swap out the HP-1 filter and report back?

Now I'm starting to look more closely at the 2nd IF (21.4Mhz) crystal filtering too.
I'm sure there would be merit in going to a much tighter, multipole 2nd IF filter. And, with a little tweaking to interstage amplifier gain, there shouldn't be any sacrifice in sensitivity despite the slightly higher bandpass attenuation of the multi-pole filter.

I don't think there would be much benefit in cascading the 1st IF (380Mhz SAW filters), but you never know :)

Bottom line is that the more crud you can filter out before the demodulation stages, the better these scanners should perform. I doubt that these mods will improve simulcast interference problems, but I have no doubt that some of the problems people are experiencing on crowded trunking bands are due to other interference modes such as adjacent channel and in-band signal overload, that should be improved by tightening up the IF filtering.

Rick
 

Boatanchor

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I should point out, that the more scanner owners become aware of these important issues, the more likely it is that manufacturers will place a higher priority on them in future designs and models.

This has become evident in the Ham radio world over the last ten years or so, with manufacturers concentrating more and more on the raw RF performance of their products. Features such as roofing filters, single IF architecture and figures highlighting 3rd Order Intercept, IP3 as well as sensitivity numbers are now routine in product brochures. Ham manufacturers now know that when dropping the big ones on new products, consumers are looking behind the flashy colour displays and rows and rows of knobs and buttons. Sure, bells and whistles are important, but if you don't get the RF stages right, you end up with an impressive looking paperweight!

Lets make sure that the next generation of scanners are designed properly!
We need to demand that manufacturers allocate a little more time and maybe only another $10-$20 on parts, to bring the RF performance up to where it should be, instead of simply recycling sub-standard RF designs and adding new User Interfaces and features, then expecting us to drop 600 big ones on a receiver that essentially hasn't progressed much (RF wise) from units produced 15 years ago!

Rant over :)
 
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vince48

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I should point out, that the more scanner owners become aware of these important issues, the more likely it is that manufacturers will place a higher priority on them in future designs and models.

This has become evident in the Ham radio world over the last ten years or so, with manufacturers concentrating more and more on the raw RF performance of their products. Features such as roofing filters, single IF architecture and figures highlighting 3rd Order Intercept, IP3 as well as sensitivity numbers are now routine in product brochures. Ham manufacturers now know that when dropping the big ones on new products, consumers are looking behind the flashy colour displays and rows and rows of knobs and buttons. Sure, bells and whistles are important, but if you don't get the RF stages right, you end up with an impressive looking paperweight!

Lets make sure that the next generation of scanners are designed properly!
We need to demand that manufacturers allocate a little more time and maybe only another $10-$20 on parts, to bring the RF performance up to where it should be, instead of simply recycling sub-standard RF designs and adding new User Interfaces and features, then expecting us to drop 600 big ones on a receiver that essentially hasn't progressed much (RF wise) from units produced 15 years ago!

Rant over :)

Boatanchor, could not agree with you more.

Vince48
 

pro92b

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Lets make sure that the next generation of scanners are designed properly!
We need to demand that manufacturers allocate a little more time and maybe only another $10-$20 on parts, to bring the RF performance up to where it should be, instead of simply recycling sub-standard RF designs and adding new User Interfaces and features, then expecting us to drop 600 big ones on a receiver that essentially hasn't progressed much (RF wise) from units produced 15 years ago!

Rant over :)

Today's radios are cost-cut designs that are inferior to radios from 15 years ago in my view. Adding more bells and whistles while providing a worsening basic radio is the wrong trend and I agree with you 100%.

The 50G filter in my 996T tracks EDACS without error and improves analog conventional signals significantly. So I see improvement all around - thanks for bringing this update to our attention.
 

KevinC

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Thanks Kevin for the offer- I'm sure it will arrive today :D
I will have some spares also. Most of my radios have dual filters already. I took them all apart to check. So maybe, if the forum moderator doesn't mind, we can use this thread as a filter swap fest when the time comes. Or we can start a new thread to share our extras.
Happy Mothers day everyone.
Bob

Did you receive yours yet?
 

leeljs

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murata filters

If there are any extras out there I can use one.
 

tumegpc

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Filter mod on HP-1

I completed the filter mod in my HP-1 and after a couple days of monitoring P25 Simulcast I'm happy to say I'm impressed. Less distortion or chop and consistently receiving more channels . Under Trunk System Analyzer the quality of my P25 Simulcast has increased.
 
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mibzzer15

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After seeing some of the feedback now, does anyone else have any extras? I would be interested in 2 of them if possible. Thanks! Just PM me.
 

Boatanchor

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I completed the filter mod in my HP-1 and after a couple days of monitoring P25 Simulcast I'm happy to say I'm impressed. Less distortion or chop and consistently receiving more channels . Under Trunk System Analyzer the quality of my P25 Simulcast has increased.

Those of you who have done the HP-1's, how do you find the squelch setting after the mod?

After modding my 396XT and 996XT's, I find I need to turn the squelch up to around 10 or even a little higher, whereas pre-mod, the setting was typically 2 or 3.

Its not a problem, just an interesting side effect of reducing the filter bandwidth.
 
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