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Message |
    
Vanillagorilla
Advanced Member
Username: Vanillagorilla
Post Number: 678
Registered: 4-2005
| | Posted on Saturday, July 22, 2006 - 4:35 pm: | 
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Thought I'd throw some old school tech questions out there.
Just picked up an SBE Sidebander III model 18CB. Its 23ch crystal controlled mobile featuring USB/LSB only. Thought is was cool..looked like new and price was right. Modulation is crystal clear and total fwd swing is around 10w with the stock mic.
Aside from looking for ANY info available like which of the two VRs is the AMC...I thought since it was only a 23CH thereby decreasing my chances of using it regularly except for the CEF net I might like to find xtals for 27.385. First...did they make xtal controlled 40ch rigs? A friend has bags and boxes of crystals for me to sift through if I have a chance of finding them.
Second..how do I know which are which as far a freq goes? I see them stamped with 11.900 or 11.905? What is this and what would be 27.385?
Are there two crystals for each channel? TX/RX?
Here comes the TOP stupid question...Any difference between sideband and AM crystals?
Sorry..new to the OLD crystal scene!
Any help on the radio or subject would be great!
Thanks
Hank CEF559 |
Hollowpoint445
Senior Member
Username: Hollowpoint445
Post Number: 1312
Registered: 6-2004
| | Posted on Saturday, July 22, 2006 - 6:14 pm: |
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Yes, they made 40 channel crystal synthesized rigs - I own one. It's also got an air variable capacitor for the clarifier circuit - it's unusual to say the very least.
Crystal synthesizing varies from chassis to chassis. Usually there will be a two sets of crystals similar in frequency that mix to produce the 23 (or more) channels. How your radio does that might be very specific because it's an unusual animal in that it's only SSB.
No, there is no difference between SSB and AM crystals. All the crystals do is create the oscillator frequency. That is not usually specific to the mode. However, there are some older radios that used 3 crystals to produce offsets for each mode even with a PLL. The Uniden 858 SSB chassis use this method.
For help with learning about crystal synthesis I suggest you read my favorite CB book:
http://www.copperelectronics.com/cgi-bin/checkitout/checkitout.cgi?catalogSTORE:CKIE:prodBKS-00020+ |
Allan
Intermediate Member
Username: Allan
Post Number: 178
Registered: 2-2006
| | Posted on Saturday, July 22, 2006 - 6:46 pm: |
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Howdy. Will a crystal mixing chart for this radio help?
www.cbcintl.com/XTALS |
Bruce
Senior Member
Username: Bruce
Post Number: 3975
Registered: 9-2003
| | Posted on Saturday, July 22, 2006 - 7:20 pm: |
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The only problem with crystals today is THEY ARE NOT CHEEP!
average price each is about 15 bucks ..... |
Allan
Intermediate Member
Username: Allan
Post Number: 179
Registered: 2-2006
| | Posted on Saturday, July 22, 2006 - 8:09 pm: |
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"A friend has bags and boxes of crystals for me to sift through if I have a chance of finding them."
Great friend! |
Vanillagorilla
Advanced Member
Username: Vanillagorilla
Post Number: 679
Registered: 4-2005
| | Posted on Saturday, July 22, 2006 - 8:52 pm: |
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Hollowpoint...just got the book for fathers day. Suppose I missed that chapter...
Allen..searching the net I did find that site for my radio but when I clicked the link I got some encrypted notepat stuff? Hmmmm. Did learn Sams #61 is my book though! The friend I mentioned has the complete library with extras. Looks like another favor I need to ask He owes me anyway... His moonraker is finally UP.
(BTW..Allen...didn't forget the pictures of the mic for you...just busy and wife is trying to use a new camera with the computer...long story but I'll get to it!)
As for how this SBE is set up..without pictures at this point:
There are 10 installed and 2 empty sockets...in other words..looks like there should be 12 xtals in all? Maybe not... Have not yet tried to test to see if all 23ch exist.
Also visible is a Crystal Filter "frequency 7.8MHz" part#. 16-1178-001B. Serial# 3Q1043 Looks like it says Nikon Dergyc Co. ltd...hard to read the script.
Directly behind the xtals is 10 var caps...freq adj? I won't screw with those until I find a way to read the freq accurately. Right now checks come back as spot on and clear.
Now wondering what those 2 empty sockets could be for or if they're just leftovers and not to be used.
Again..I'd like to know what numbers to look for to find my other freqs if possible. Suppose
I'll try to get hold of a Sams book and REread the Screwdrivers experts book.
Thanks for the input guys! Any more would always help. If I could replace a certain bank with anything including .385 I would package and label the removed ones and tape them inside the cover.
Hank CEF559 |
Vanillagorilla
Advanced Member
Username: Vanillagorilla
Post Number: 684
Registered: 4-2005
| | Posted on Tuesday, July 25, 2006 - 2:06 pm: |
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Well thanks to some off forum help I downloaded the crystal chart and a friend DID have an extra copy of SAMS #61! Shazam!
Also exploring the possibility of a VCO. Found out a Siltronics or PAL 90-1 is the one I need.
If nobody minds I figure I'll keep this thread rolling for future "search" users and for anyone interested.
Anyone with further input or suggestions is MORE than welcome to chime in.
Gotta go read Sams and learn something
Hank CEF559 |
