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Message |
    
Crossbow
Junior Member
Username: Crossbow
Post Number: 33
Registered: 1-2002
| | Posted on Thursday, March 03, 2005 - 11:19 am: | 
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does anybody know or where i can find out how to tell the difference between a 10.7 IF crystal and a 10.8 IF crystal or better, how do you tell the difference between a radioshack and a bearcat scanner crystal. |
Bruce
Senior Member
Username: Bruce
Post Number: 2302
Registered: 9-2003
| | Posted on Thursday, March 03, 2005 - 12:36 pm: |
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10.7 is standard ..... never seen a 10.8 ....
Most crystals are clearly marked ..... Most VHF ( HIGH ) crystals are 3rd overtone and are multiplyed times 3 ..... so a crystal for say 154.600 This crystal frequency would be F( crystal ) = 154.6-10.7 / 3 =47.96 MHZ. Now a few are cut on the high side F=154.6+10.7/3= 55.1 mhz.
NOTE.....
VHF low crystals are 3dr overtone and are not multiplyed.
UHF crystals ( 440 - 475 MHZ )most are TIMES 9
However the first IF is not always on 10.7 it can be on 21 or even 50 mhz you would find that in the book on the radio ....
F ( crystal ) = 450.000- (IF ) /9
Cost is about 12-18 dollars per crystal
You need some try JAN Ft Myres Fl or Sentry in Chicksaw OK. I have used both for more than 30 years BOTH are good
Bruce |
Coyote
Intermediate Member
Username: Coyote
Post Number: 136
Registered: 11-2004
| | Posted on Thursday, March 03, 2005 - 2:14 pm: |
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BearCat Scanners use the 10.8Mhz IF
Interchangability of Scanner Crystals
"Regency" & "Bearcat" crystals are not the same; however you can use BC (10.8MHz IF) crystals in place of TMR (10.7MHz IF) crystals (& vice-versa) when you consider the IF frequency to determine the frequency it would receive in a different brand scanner:
Regency 42.580 TMR receive =(crystal 3rd overtone 53.280)= Bearcat 42.480 BC receive
Regency 155.190 TMR receive =(crystal 3rd overtone 48.1633)= Bearcat 155.290 BC receive
Regency 460.700 TMR receive =(crystal 3rd overtone 50.0000)= Bearcat 460.800 BC receive
Regency Low-band crystal compatibility list. Third Overtone crystal frequency =channel frequency +10.7Mhz; series resonance -450Hz; HC25/u holder.
Example: Chan freq=40.000Mhz +10.7Mhz=50.7Mhz. Various brands may be labeled as Type 992, HL-44, JK-1, MRL-1, MCS-1, RXD-1 TME, TMR
Regency High-band crystal compatibility list. Third Overtone crystal frequency=channel frequency -10.7Mhz divided by 3; series resonant -450Hz; HC25/u holder.
Example: chan freq=155.000Mhz-10.7Mhz =144.3Mhz divided by 3 =48.100Mhz.
Various brands may be labeled as Type 903, A, HL-44, MCS-1, MRH-1, PFC-1, RXD-1, TME, TMR
Regency UHF-band crystal compatibility list. Third Overtone crystal frequency =channel frequency -10.7Mhz divided by 9; load capacity 18pf; HC25/u holder.
Example: chan freq =458Mhz -10.7Mhz divided by 9 =49.7000Mhz. Various brands may be labeled as Type 911, MCS-1, TME, TMR
Labels on Scanner Crystals:
Crystals made for 10.7Mhz IF scanners including "Regency" may be branded 10.7 CCI, 302-500, 903, 911, 992, A, A-4, ECS-1, ECSH-1, ECSL-1, ECSU-1, HL-44, JK, JK-1, MCS-1, MRH-1, MRH-6, MRL-1, MRU-1, RCD-1, T417 TC-L17, TME, TMR, TN-1, PEI, PFC-1, RXD-1,
Crystals made for 10.8Mhz IF scanners including "Bearcat" may be branded 10.8 CCI, 905, 912, A-135, A-135-2, B, BC3, BC-E, BCL, BCM, BCT, BRMU, C9-86, ECS-2, ELECT-3, JK-5, MCS-2, MRH-2, RCD-2,
Hope this helps some. |
2ec837
Member
Username: 2ec837
Post Number: 64
Registered: 12-2001
| | Posted on Thursday, March 03, 2005 - 2:52 pm: |
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10.7 IF Cystals are used in Realistic,Regency and most other crystal scanners.10.8 IF crystals are used in Electra Bearcat scanners and maybe a few others. |
Bruce
Senior Member
Username: Bruce
Post Number: 2304
Registered: 9-2003
| | Posted on Thursday, March 03, 2005 - 11:06 pm: |
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This leaves the unanswered question .....
Unless you had only a few frequencys why would you even bother with crystals? |
Coyote
Intermediate Member
Username: Coyote
Post Number: 138
Registered: 11-2004
| | Posted on Friday, March 04, 2005 - 5:30 am: |
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Bruce, good question, most people wouldn't considering what the new scanners will do. I happen to have a crystal controlled Craig 4350a. I guess it's for the nostalgia, or maybe its to watch the pretty lights flashing. Where I live there really aren't but a few frequencies, we only utilize 3 channels here. One for city/county cops, one for fire and one for EMS, so it works out fine for me. I do have a newer Pro95 that is used most of the time but I still hold on to the old one for the pretty lights.  |
Crossbow
Junior Member
Username: Crossbow
Post Number: 35
Registered: 1-2002
| | Posted on Saturday, March 05, 2005 - 8:36 am: |
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It's the lights. Thanks for the info. How about the ones that have the numbers stamped on them, is that there frequency or do i use the overtone method to figure out. I was given some old scanners and big box of crystals. I guess some of the crystals are for 2-ways because they have an R or T before frequency numbers. I havn't found any that work yet doing it my way. So maybe I will find some.
thanks Guys for the info |
Hotwire
Intermediate Member
Username: Hotwire
Post Number: 153
Registered: 1-2005
| | Posted on Saturday, March 05, 2005 - 11:53 am: |
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Hey crossbow! Hang on to those transmit crystals. Dont let them fall into the wrong hands. |
Coyote
Intermediate Member
Username: Coyote
Post Number: 142
Registered: 11-2004
| | Posted on Saturday, March 05, 2005 - 1:39 pm: |
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Crossbow, Do you know what freq's are being used in your area? Need to know that to start. Then you need to be able to determine what type crystals they are(i.e. 10.7 or 10.8) I have about 100 crystals both TX and RX that I can't use because there is no one using the freq's in my area. Email me so I can point to a site where you can find out the freq's used in your area if you don't already know. I might have some you need and vise versa. smiller1@dtccom.net (please don't anyone start spamming me. j/k LOL) |
Patzerozero
Advanced Member
Username: Patzerozero
Post Number: 540
Registered: 7-2004
| | Posted on Saturday, March 05, 2005 - 1:51 pm: |
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'Where I live there really aren't but a few frequencies, we only utilize 3 channels here.'
no offense intended, coyote, but the joys of rural america. MY LOCAL police precinct alone uses at least 10 channels, there are 4 other precincts within 'incident-that-could-affect-you' range, so there's more. then the local sheriffs dept & their freqs, & multiple marine enforcement agencies with multiple freqs, & a dozen or more FD's with several for each, HELP!!!
before my police precinct went apco, my old 20 channel bearcat wore out the buttons inputting freqs during brush fire season, plane crash, boating season,etc. even in the old crystal days we kept a box around with 20 or more extras & the cover unscrewed so you could 'quick-change' during times of emergency! |
Coyote
Intermediate Member
Username: Coyote
Post Number: 143
Registered: 11-2004
| | Posted on Saturday, March 05, 2005 - 5:01 pm: |
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Patzerozero, no offense taken. There are more channels here being used, but I don't care to listen to the phone crew's, the water dept, etc... LOL. I can listen to most of the surounding county's too though, but even they only use about 3 channels for emergency transmission's per county. |
Racer_x
Intermediate Member
Username: Racer_x
Post Number: 105
Registered: 2-2005
| | Posted on Saturday, March 05, 2005 - 7:05 pm: |
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I don't know how anyone ever used a crystal scanner. I've never seen one with more than 10 frequencies and I can't even imagine limiting my listening to only 10 frequencies. I'd have to have a dozen of them, but that's not a bad idea anyway. I haven't found any at local yard sales or hamfests that have my county control channel, but if I do I'll buy it in a minute so I can free up a programmable scanner for other use.
I like to have a scanner tuned to my county control frequency so I don't miss anything there, while I have another scanner searching for other things. And I like to have a scanner for each of the services I monitor so I don't miss anything going on there.
Before I came to the realization that I needed many scanners instead of one big one, I bought a couple of 1000 channel scanners. I never thought that I could fill those babies up, but I did in less than a month. Unfortunately even though I had all the freqs that I wanted to listen to, it didn't work as well as I had hoped. Now I use them as the radios I take with me when I leave home, but at home I listen to individual scanners. |
Bruce
Senior Member
Username: Bruce
Post Number: 2308
Registered: 9-2003
| | Posted on Saturday, March 05, 2005 - 8:47 pm: |
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Everyone ............
I love the smell of burninng tubes and tweeking in that old FT-243 crystal too but the cost is so high that with the fact you can buy for under $50 a good used 20-50 ch scanner infact i just last year tossed out my last one after i had several trunking ones of 300 ch or more.
Ah fot thoes good old days some time ill have to take a photo of my Standard 146 which i bought in july of 1970 and it still works and i still use it 5 ch crystal controled ..... a real BRICK and 4 lbs!
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Bruce
Senior Member
Username: Bruce
Post Number: 2308
Registered: 9-2003
| | Posted on Saturday, March 05, 2005 - 9:06 pm: |
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My trusty Standard 146 2 Meter HT ( 1970 )
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Coyote
Intermediate Member
Username: Coyote
Post Number: 145
Registered: 11-2004
| | Posted on Saturday, March 05, 2005 - 9:17 pm: |
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Bruce, just exactly how much stuff have you thrown away over the year's? Kind of make's me wish I was your trash collector.  |
Bruce
Senior Member
Username: Bruce
Post Number: 2308
Registered: 9-2003
| | Posted on Saturday, March 05, 2005 - 9:40 pm: |
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When we left the other house 2 55 gal trash cans most was tube stuff and old 23 ch cb's
( the wife said get rid of it ) |
Bc910
Intermediate Member
Username: Bc910
Post Number: 426
Registered: 7-2004
| | Posted on Sunday, March 06, 2005 - 11:27 am: |
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Bruce!
Your making me cry!
BC |
Bruce
Senior Member
Username: Bruce
Post Number: 2312
Registered: 9-2003
| | Posted on Sunday, March 06, 2005 - 12:30 pm: |
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Coyote
I still have several old crystal bound ham radios like my HR-6 but why even try to play with them?
My Alinco DR-M06 has 99 memories with tone and offset built in the HR-6 has 12 channles at 45 bucks EACH and no tone. The last crystal radio i restored was a late 60's 6 meter HT its almost as big as the standard 146 but was just a wim on my part ( A EXPENSIVE ONE ) and this one ch radio wound up costing me 75 bucks! |
Coyote
Intermediate Member
Username: Coyote
Post Number: 147
Registered: 11-2004
| | Posted on Sunday, March 06, 2005 - 2:25 pm: |
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Bruce, Well, just remember me next time the wife makes you start throwing things away. |
Bruce
Senior Member
Username: Bruce
Post Number: 2315
Registered: 9-2003
| | Posted on Sunday, March 06, 2005 - 6:47 pm: |
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I will and SHE WILL ..... |
Coyote
Intermediate Member
Username: Coyote
Post Number: 148
Registered: 11-2004
| | Posted on Sunday, March 06, 2005 - 10:19 pm: |
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Mine hasn't made me start throwing any of mine away yet. But she's made it clear I don't need any more.
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Hotwire
Intermediate Member
Username: Hotwire
Post Number: 166
Registered: 1-2005
| | Posted on Monday, March 07, 2005 - 8:49 am: |
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Hey Patzerozero you mentioned apco in one of your posts. What is that?
In my area Indy law enforcment is on 800meg. The surrounding countys use VHF. My county,Johnson, used to use VHF but now went somewhere else far beyond 800meg.
I was told that this new band that they use is new and exclusive to law enforcment. I was told about 5 years ago that Johnson county was the first to go there. I was also told back then that I could not monitor unless I had owned some real expensive type reciever.Ever since then I am not able to monitor my citys police.Again I am not talking about 800meg trunked. This is something new to me. thanks |
Inspector
Intermediate Member
Username: Inspector
Post Number: 136
Registered: 12-2001
| | Posted on Monday, March 07, 2005 - 7:17 pm: |
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Hotwire, They may have gone to an APCO-25 system...this is digital and you would need one of the new expensive DIGITAL capable trunking scanners. The State-wide system they are trying to implement in Indiana is called the SAFE-T network. I'm not too familliar with the system as it hasn't reached the northern third of the state yet, so I don't know if it is digital or not but I DO know it is a trunked-system. |
Bruce
Senior Member
Username: Bruce
Post Number: 2321
Registered: 9-2003
| | Posted on Monday, March 07, 2005 - 8:11 pm: |
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Hotwire .... bummer if they went digital ... i have 2 non digital trunkers here just got rid of 2 more and Sarasota county just south of me went digital ..... digital scanners is not cheep. |
Hotwire
Intermediate Member
Username: Hotwire
Post Number: 167
Registered: 1-2005
| | Posted on Tuesday, March 08, 2005 - 11:21 am: |
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I think they did go digtal. It was in the paper a while back that the local police who went digital was having problems. They could not communicate with our sherrif or the state troopers because it. So I guess until everybody upgrades the decided to use both the digital and Vhf band radios. Hey Bruce! Say they are digital. What type of antenna would I see on the police cruisers. How many inches tall for digital police element?
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Bruce
Senior Member
Username: Bruce
Post Number: 2327
Registered: 9-2003
| | Posted on Wednesday, March 09, 2005 - 7:03 am: |
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10101010 11010010 11100110
I hope that explanes digital antennas ( in 8 bit ... )
Ok kidding aside they are on the 800 range and any 800 mhz antenna should work. A 1/4 wave antenna is about 3 inches |
Hotwire
Intermediate Member
Username: Hotwire
Post Number: 172
Registered: 1-2005
| | Posted on Wednesday, March 09, 2005 - 8:56 am: |
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OK Bruce thanks |
Bc910
Intermediate Member
Username: Bc910
Post Number: 431
Registered: 7-2004
| | Posted on Wednesday, March 09, 2005 - 4:43 pm: |
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Hot,
I am 100% positive that Johnson county is digital
A digital scanner will cost 'ya right around $500.00! OUCH!
BC |
Hotwire
Intermediate Member
Username: Hotwire
Post Number: 177
Registered: 1-2005
| | Posted on Thursday, March 10, 2005 - 9:01 am: |
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Yo Bc do you know anywhere around here ssomebody can buy one? That price is way better than I been told at upwards of 2 grand!!!! MEGA OUCH!!!!
Radio Shack told me. Go figure. Speakin of Rat shack,I remember back when they were so knowledgable about scanners and radios. Heck they even hired hams to work there. Go there now and ask a simple radio question and get looked at like your stupid or something. |
