| Author |
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Jwhipple
| | Posted on Wednesday, June 26, 2002 - 1:16 pm: | 
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I read 307's review on the AS100 switch - sounds just like what I am looking for! I have 2 radios - one of them has a really wide frequency range, and the other does SSB/FM but only 40 channels. I realize this switch allows you to use 2 radios with the same antenna, but will you be able to have both radios turned on and receiving at the same time?
Also, I read elsewhere here in the forums that Copper ran out 6 months ago before the post was put up - but yet I see the AS100 switch on the product list - is Copper still carrying these?
Thanks!
JW |
Taz
| | Posted on Thursday, June 27, 2002 - 10:09 am: |
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yes both radios will receive at the same time. only one can transmit at the same time.
Taz |
Jwhipple
| | Posted on Thursday, June 27, 2002 - 8:50 pm: |
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I guess it would be safe to assume then that they could be both running on seperate channels independant of each other?
If one is listening on Channel 9, and the other transmitting on channel 19, will the one on channel 9 still be able to Rx? I would think not but I figured it can't hurt to ask!
Thanks again!
JW |
Snapperhead
| | Posted on Thursday, June 27, 2002 - 6:58 pm: |
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Hey Taz,
Does that switch change your SWR at all?.....
I was thinking about getting one too..... |
Highlander
| | Posted on Thursday, June 27, 2002 - 2:18 pm: |
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Only one radio can receive at a time. |
Barefoot
| | Posted on Thursday, June 27, 2002 - 1:43 pm: |
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After you transmit you lose most of the receive on the second radio |
Ss8541
| | Posted on Thursday, June 27, 2002 - 11:08 pm: |
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ok, who is right here??? i made a post about 'multicoupling' rxers over at another site and was told that the as-100 was -not- capable of simultaneous rx(multicoupling of rxers). taz says here it is, and highlander says it isn't. i feel that highlander is right for certain reasons, but i would like to know from someone who can put this to rest for sure(like someone from copper, or someone who owns one). |
Taz
| | Posted on Friday, June 28, 2002 - 3:21 am: |
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well, i dont own one but i have been old it dosent affect swr.
hmm, im not sure who is correct but i have been told that both can receive at the same time but i am not sure since i do not own one |
Jwhipple
| | Posted on Friday, June 28, 2002 - 11:53 am: |
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LOL Glad I asked! Didn't realize this was something that would cause such a stir! Thanks guys, looking forward to more info! |
Jwhipple
| | Posted on Friday, June 28, 2002 - 5:19 pm: |
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I figured I would add a little fuel to this fire - I just found the following thread where DA MAN himself, 307, says that it does work on both... http://www.copperelectronics.com/cgi-bin/discus/board-auth.cgi?file=/34/10352.html |
Taz
| | Posted on Friday, June 28, 2002 - 8:00 pm: |
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i thought the point of the device was to listen to more than one channel at the same time!
thats what i would use it for~! |
Jwhipple
| | Posted on Saturday, June 29, 2002 - 12:19 pm: |
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That's mainly the point of me wanting one - I want to monitor my usual SSB haunts on the one radio that has the SSB on it, while I monitor my usual AM channels on the other radio that has the extra channels... |
Barefoot
| | Posted on Saturday, June 29, 2002 - 9:13 am: |
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When you first turn both radios on you can receive on both.The first time you key up you lose receive on the other radio |
Taz
| | Posted on Saturday, June 29, 2002 - 2:30 pm: |
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yeah while you are keyed up. but when you un-key your receive comes back |
Bigbob
| | Posted on Saturday, June 29, 2002 - 4:51 pm: |
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Barefoot are you saying you're txing into the rx of the other radio thus blowing it's reciever strip? |
Ss8541
| | Posted on Saturday, June 29, 2002 - 11:11 pm: |
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according to the merc's post in the link given, he has tested 3 and none have rxed at the same time. i have spoken with him in the past, and he is a straight shooter. i have never spoken with 307, but i don't see him saying it does do it, just to say it does. it may be possible that there is an older version that does 'multicouple' and a newer version that does not.
to make a long story short(atleast as short as possible), if the as-100 is capable of 'multicoupling' the rxers, the rx input level at each radio will drop by 3db(3db = 1/2). so you are losing half the signal that is coming down your antenna(it is split between the two rxers even if they are on different ch's). you are actually losing more than 3db because there is no 'matching' of impedance. both rx ports are 50 ohms. when you split these between 2 coax lines the impedance becomes 25ohms. and then throw in the insertion loss of the device itself, the extra connectors needed, and you could be close to a 4db(60%) loss at both rxers. to do this correctly you need something called a multicoupler to keep each rx port at 50ohms. there are multicouplers that can tie up to 64 rxers into one antenna. even with the multicoupler, you still need a preamp/preamps to offset the losses.
if you have a pre-amp between the as-100 and antenna or one in an amp that is between the as-100 and the antenna, then this is not a problem. i don't care much for the 'cb' type preamps(stand alone or in an amp) because they are made cheaply. they are noisy because of this cheap design, and amplify signals all across the rf spectrum(no pre-selector/band pass filtering). these out of band signals can mix with other out of band signals and cause imd or image problems on the freq you are monitoring. if strong enough they can desensitize the radios rxer and you may miss stations that you would have heard -without- the preamp.
do i use pre-amps?, sure, but not when skip is very strong for the reasons i listed above. well i even use them then also, but i understand the associated problems so it depends on the situation. |
Ss8541
| | Posted on Sunday, June 30, 2002 - 12:12 pm: |
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i forgot to add last night that there are some preamps out there that do have bandpass filtering. i know that the lt-1 and ep-27 has this. also atleast one of the klv amplifiers has this type of preamp. i use a ep-27 that i got in a trade, and it works well with its -30db to +30db gain adjustments and 26-30mhz bandpass. when i get time i would like to retune this with a comm analyzer for a tighter 26.5-28.5mhz split, or the 25-29mhz area and see how that works since more cbers would use this split than the 26-30mhz factory split. not really sure how either would work out since i have only taken the cover off once to look inside. and then it was just to look, didn't really take time to see exactly how it was designed(would have to pull board out).
anyway thought i would throw this little tid bit in about these preamps. |
Jwhipple
| | Posted on Saturday, July 06, 2002 - 1:12 pm: |
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Well I broke down and bought one brand new off of EBay... It arrived yesterday and I will let you all know how it works... I figured that even if the input to each radio is cut in half, I could live with having to turn on my pre-amp... |
Jwhipple
| | Posted on Monday, July 08, 2002 - 8:34 pm: |
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Ok here's the scoop... When I first hooked it up, BOTH radios could receive...
BUT, the instant I keyed up on one of them that went right out the window... The transmitting radio's receive was 100% just as it was before, however, radio #2 was severely cut down - but YES, it WILL receive..
I then moved to radio #2 and keyed up - receive was now 100% on that one, and cut down on radio #1...
I am still testing with the pre-amp theories, but I am wondering about the practicality of using it - afterall, who wants to be going down I-95 and have some truck driver who is pushing 1600 or so watts key up on the same channel I am on with the 100% receive radio while they have the pre-amp turned on? Sounds like that idea stinks - literally - I can smell the smoke coming from my radio now!
Ok folks, any other ideas?
Overall I still like the AS100 - my secondary radio has a nice, quick scan function on it that runs through a 40 channel band in about 3-4 seconds, nice to be able to home in on whatever channel someone is Tx'ing on that is bleeding over onto the channel that I am on... |
Barefoot
| | Posted on Tuesday, July 09, 2002 - 11:43 am: |
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You are right about the way the receive drops after you key up |
Insider
| | Posted on Tuesday, July 09, 2002 - 10:27 pm: |
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Still, it sounds like a good product. I think I have a simple solution that will solve the problem for the average CBer.
If you need to use a radio in another room, inform the person or persons you are talking to that you will be changing radio's and expect a brief, but lightning fast key up to restore your receive. If you key it real quickly, I bet no one will even notice, but it's better to be polite and give advance notice.
Also, I've heard some say in other places that they'd like to see one that could handle more power so they can use a big amp with it. Why not put the AS 100 before the amplifier, that way you can use two radios with one amplifier. |
Ss8541
| | Posted on Wednesday, July 10, 2002 - 10:27 pm: |
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insider, i never said it was not a good product. i just gave a warning to the results of 'dual rx'/multicoupling. from what i see the as-100 does -not- 'dual rx'. and even if it did a 3db loss is only 1/2 a s-unit. will not amount to jack to a 2s-unit to 30db over s9 signal, but can make a world of difference to a 1 s-unit signal.
-but-, what we have to keep in mind, is that relay contacts are -very- close in the 'open' mode. this would account for why the radio that is not in the 'on' mode still hears but at a lesser level. it looks as though the 'open' relays contacts are close enough for capacitive coupling of the rx signal to the radio. it is capacitively passing the rx, but at a much lesser level.
i use a test adapter that works just like this to find system sensitivity(different from radio sensitivity since the antenna system is included in this test). |
Insider
| | Posted on Thursday, July 11, 2002 - 1:00 am: |
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Ss8541:
Sorry for the confusion. I was just making a statement in general that despite the lack of receive on both radios, the AS100 is still a useful product. After reading this thread, I'll most likely buy one for my setup. |
Barefoot
| | Posted on Friday, July 12, 2002 - 11:57 am: |
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If anyone wants a good used one I,ll sell mine |
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