Quantar in cabinet repeat audio is low

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maxjam
Posts: 124
Joined: Fri Sep 07, 2001 4:00 pm

Quantar in cabinet repeat audio is low

Post by maxjam »

I have a R2 Quantar that I moved to the 2m band. Adjusted up the rx front end, and went through the alignment procedures for tx freq, and deviation adjust. Just minor changes were made to touch it up. However, the in-cabinet repeater audio is less then 1 kHz. Were are I missing the repeat audio adjustments?

thanks.
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xmo
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Re: Quantar in cabinet repeat audio is low

Post by xmo »

Check the part number of your station control module.

We have found that stations using the CLN7558A EPIC-III station control module have very low TX audio when programmed out of band.
maxjam
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Re: Quantar in cabinet repeat audio is low

Post by maxjam »

Found a CLN7558C card. Any cures?
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xmo
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Re: Quantar in cabinet repeat audio is low

Post by xmo »

Replace the EPIC-III card.

Other EPIC card versions show up on ebay from time to time.

You will need to consider firmware version compatibility when you replace the station control board. You can't transfer the firmware from the EPIC-III to any of the other version control modules becasue the SIMs are terminated differently, so you will probably have to use the firmware version that comes with the card you buy.

There is a table of versions in the RSS manual [and CPS help file].

The wireline and station control versions need to correspond closely, exciter is less of an issue.
W4CLL
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What radios do you own?: APX7000 SL7550 XTL5000 XPR's

Re: Quantar in cabinet repeat audio is low

Post by W4CLL »

maxjam wrote:I have a R2 Quantar that I moved to the 2m band. Adjusted up the rx front end, and went through the alignment procedures for tx freq, and deviation adjust. Just minor changes were made to touch it up. However, the in-cabinet repeater audio is less then 1 kHz. Were are I missing the repeat audio adjustments?

thanks.
I have a new R2 VHF Quantar. Re-tuned it as in the above
quote with the same low audio. My approach is to change
the Exciter Board Resistor Rom (Exciter Type ID) which
I believe is just SMD resistors, maybe 000 shorting
resistors to present to the exciter cpu which of 8
band/range choices the exciter could be setup for.
8 choices can be done with three jumpers. As I do not
have the Moto service manual or the part Number to order
it, I will just reverse eng the cpu cage and id which
input bits can be set logic high or logic low. Once I can
make my exciter report to the EPIC-III that I have a R1
VHF exciter I hope this may solve the problem. Comments?
Chuck - W4CLL http://www.w4cll.com
73, DE W4CLL
"May the Digital be with you"
http://www.w4cll.com
W4CLL
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What radios do you own?: APX7000 SL7550 XTL5000 XPR's

Re: Quantar in cabinet repeat audio is low

Post by W4CLL »

I now know how to make the Quantar Exciter & PA
module report to the Epic-III controller that they are [R-1]
modules. My Quantar now has normal audio and works
very well. I purchased the Motorola Service manual. Two
very thick books. About 18 Lbs. and approx $244.xx so
not cheap! On the Exciter, you will need to move one smd resistor from
one set of pads to another set of pads. On the PA module, you
will need to remove one (000) shorting smd and replace it with a 10K smd
which goes to Gnd. You will also need to add a 20.5K smd resistor going up
to +5v. At this point the PA & Exciter modules should report to the Epic-III
module (R-1) values. There is one other issue. You will now need to make the
Exciter module select the opposite VFO. If you fail to preform this step, you
will not have Exciter "Lock". One other note: I use an electronic soldering iron
, good Kester .020 Dia. solder and very small solderwick.

73, DE W4CLL
"May the Digital be with you"
73, DE W4CLL
"May the Digital be with you"
http://www.w4cll.com
VE3TUH
Posts: 279
Joined: Fri May 24, 2002 3:14 pm
What radios do you own?: more than I should...

Re: Quantar in cabinet repeat audio is low

Post by VE3TUH »

Ok, I am interested in making my range 2 cards report as range 1. I do not have the audio issue with my repeaters, but I found that I did have to retune the rx vco's slightly in order to achieve vco lock at my rx freq of 144.690.
Can you provide the component numbers of the parts you are moving around, please, or a description of where they are on the card.
Did you do the reciever as well?
How exactly do you cause the exciter to select the opposite vco?
W4CLL
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What radios do you own?: APX7000 SL7550 XTL5000 XPR's

Re: Quantar in cabinet repeat audio is low

Post by W4CLL »

VE3TUH wrote:Ok, I am interested in making my range 2 cards report as range 1. I do not have the audio issue with my repeaters, but I found that I did have to retune the rx vco's slightly in order to achieve vco lock at my rx freq of 144.690.
Can you provide the component numbers of the parts you are moving around, please, or a description of where they are on the card.
Did you do the reciever as well?
How exactly do you cause the exciter to select the opposite vco?
Since you have not included your Exciter and PA Motorola Part numbers, Here is what I did.

My Exciter is: TLD9832D (CLD1280A)
Move 1K resistor from R-3701 to R-3700. Added jumper from Q3260 emitter to collector
thereby ensuring that the upper Freq VCO will be used in all cases! I will need to confirm this
the next time I go over to the tower though.

My 125 Watt PA is: TLD3102G
Change R-4163 from "000" 0 Ohm to 10K resister.
Add a 20.5K resister to the open R-4162 pad. (I used 22K here!)
73, DE W4CLL
"May the Digital be with you"
http://www.w4cll.com
KE5KAF
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Re: Quantar in cabinet repeat audio is low

Post by KE5KAF »

I have a VHF Quantar with a Range1 Receiver, a Range 1 Power Amplifier (25 watts) and a Range 2 Exciter.

At close range the audio passes through with no problem, or with considerable power such as a mobile radio. But with a portable less than a few miles away the audio does not pass.

I am assuming this fix/mod by W4CLL will fix this?

Are all the mods directly on this Exciter board?

Does anyone have pictures they can provide or a schematic?

Thank you
Aaron
N5VAE
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Bill_G
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Re: Quantar in cabinet repeat audio is low

Post by Bill_G »

Yours sounds more like a receiver problem Aaron. If true, then the mods discussed will not fix the problem.
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d119
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Re: Quantar in cabinet repeat audio is low

Post by d119 »

I don't think mixing an R1 PA with an R2 exciter is a good idea either. What's the station log show? Got to be all kinds of alarms in there. I'm surprised you aren't getting PA LOW/PA FAIL with that combination. Or did you open up the PA and change the jumpering to fool the station into thinking it's an R2 PA or R1 Exciter?
DarkHelmet
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Re: Quantar in cabinet repeat audio is low

Post by DarkHelmet »

W4CLL wrote:
Since you have not included your Exciter and PA Motorola Part numbers, Here is what I did.

My Exciter is: TLD9832D (CLD1280A)
Move 1K resistor from R-3701 to R-3700. Added jumper from Q3260 emitter to collector
thereby ensuring that the upper Freq VCO will be used in all cases! I will need to confirm this
the next time I go over to the tower though.

My 125 Watt PA is: TLD3102G
Change R-4163 from "000" 0 Ohm to 10K resister.
Add a 20.5K resister to the open R-4162 pad. (I used 22K here!)
So yea, this is totally the wrong way to do it. You'll end up with a science project and then some one else will see it ID as a R1 at some point, but not work across the entire band.

To move the PA from VHF R2 to R1 the only thing you need to replace is the Alcatel (RFS) circulator and change the resistor "ROM" to 3 volts on PA_ID A. The LPF/IPA/FPA are all the same. if you want to test it, remove the circulator and jumper around it. (5884911T28 may work in place of 5884911T19, or get it rebuilt for $150).

The exciter is a bit different. You will need to retune the VCO's using a couple power supplies an a spectrum analyzer.
I have not written up the VHF units yet, but I have information on converting a UHF R1 to R2 here. It's basically the same, but with easier access to the VCO.

Or you can wait till the end of the year and I'll finish my write up on VHF exciter/receiver and the preselector. Moving R2 to R1 for the preselector is going to be a :o, as it's moving it down in frequency.

Code: Select all

Part number	R1	R2		function
C3200	.01uF	.022uF		Steering line bypass
C3201	15	12	5%	High VCO reduced varractor swing, in series with varictor, 
C3202	15	10	5%	High VCO cap Fr
C3205	22	18	5%	High VCO feedback
C3207	22	18	5%	High VCO matching to buffer
c3232	12	15	5%	Low VCO cap Fr
C3433	.01uF	.022uF	5%	
L3232	10 mm 3.5 Turn	10 mm 2.5 Turn		Low VCO
L3202	10 mm 3.5 Turn	10 mm 3.5 Turn		High VCO
R3251	8200	6800	5%	Mod input divider
R3271	100	150	5%	
R3274	150	100	5%	Sets gain (shunt) across input to MMIC buffer amps
R3436	2700	2200	5%	
R3441	270	220	5%	
R3442	5600	3300	5%	
R3443	5600	3300	5%	
R3444	18	12	5%	
R3445	18	12	5%	
R3450	470	390	5%	
R3451	12000	8200	5%	
R3457	12000	5600	5%	
R3460	12000	5600	5%	
R3700	1000		5%	Exciter ID
R3701		1000	5%	Exciter ID
Also, keep in mind the schematics are backwards for showing the VCO's. High is low, low is high, Finkle is Einhorn, Einhorn is Finkle.
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