RE: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
Nate and all Mouser is the same way... www.mouser.com I have their door-stop catalog here in the shack. They do not have a minimum order, but basic shipping starts at about $8.95, so it doesn't make a lot of sense to order of you're only spending $10 or so... The shipping can eat you alive though if you're not careful. Mark - N9WYS -Original Message- From: Repeater-Builder@yahoogroups.com On Behalf Of Nate Duehr Sent: Wednesday, November 29, 2006 9:13 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it Kris Kirby wrote: > Let's see.. there's a bunch of op-amps that come to mind... there's > 'audiophile' amps out there, and there's just instrumentation stuff... > the LM324 is pretty common, as well as the LM1458 and it's cousin the > LF353 (JFET inputs). NE5532 is an audiophile part, but certainly works > as well. The TI TL082 also comes to mind as a commonly used one by hobbyists. It's available in 8-pin DIP packaging amongst other things, which for some types of components is getting more difficult by the day -- soldering SOIC's just isn't as much fun as the old thru-hole parts. Datasheet: http://focus.ti.com/lit/ds/symlink/tl081a.pdf DigiKey carries just about all of the ones folks here have mentioned... Perhaps you don't know about Digikey -- if you don't, go to their website and do a catalog request if you plan on purchasing anything electronics-related. You'll enjoy the monster the size of a phone book that shows up at your doorstep. http://www.digikey.com/ Here's JUST the Texas Instruments op-amp page from their online version of the paper catalog... http://dkc3.digikey.com/PDF/T063/0586.pdf That's just page 586 of their catalog! I'd say you have a LOT of usable options! :-) Nate WY0X
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
Kris Kirby wrote: > Let's see.. there's a bunch of op-amps that come to mind... there's > 'audiophile' amps out there, and there's just instrumentation stuff... > the LM324 is pretty common, as well as the LM1458 and it's cousin the > LF353 (JFET inputs). NE5532 is an audiophile part, but certainly works > as well. The TI TL082 also comes to mind as a commonly used one by hobbyists. It's available in 8-pin DIP packaging amongst other things, which for some types of components is getting more difficult by the day -- soldering SOIC's just isn't as much fun as the old thru-hole parts. Datasheet: http://focus.ti.com/lit/ds/symlink/tl081a.pdf DigiKey carries just about all of the ones folks here have mentioned... Perhaps you don't know about Digikey -- if you don't, go to their website and do a catalog request if you plan on purchasing anything electronics-related. You'll enjoy the monster the size of a phone book that shows up at your doorstep. http://www.digikey.com/ Here's JUST the Texas Instruments op-amp page from their online version of the paper catalog... http://dkc3.digikey.com/PDF/T063/0586.pdf That's just page 586 of their catalog! I'd say you have a LOT of usable options! :-) Nate WY0X
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
Could this possibly be another one of those transmit crystal problems? I had that same low-deviation problem with a UHF Motorola MICOR Repeater. I had a company up in Canada recrystal my channel elements, instead of using ICM, who I always used before. When I tuned up the exciter with the newly reworked element, I found that I could only get about 2 kHz deviation out of the transmitter. Having ICM recrystal the channel element with one of their crystals fixed the problem - now I can go easily to 5 kHz (and more, if I wanted it). One of those cases where I tried to save a few bux and got bit. What's that old saying that goes something like "penny wise, pound foolish?" LJ -Original Message- >From: Kris Kirby <[EMAIL PROTECTED]> >Sent: Nov 29, 2006 4:42 PM >To: Repeater-Builder@yahoogroups.com >Subject: Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev,how >can I increase it > >On Wed, 29 Nov 2006, Bob Dengler wrote: >> You can really use just about any op amp, even the old 741. For that >> one the output is pin 6, not pin 1, & the V+ supply goes to pin 7 >> instead of 8. I recommended the TLV2372 or LMC6482 because they're >> less prone to crossover distortion. >> >> If you want to order the good ones: >> >> TLV2372: Digikey: 296-12219-5-ND $1.30 Newark: 76C7976 $1.30 Mouser: >> 595-TLV2372IP $1.30 >> >> LMC6482: Digikey: LMC6482IN-ND $1.82 Newark: 41K2662 $1.92 > >Let's see.. there's a bunch of op-amps that come to mind... there's >'audiophile' amps out there, and there's just instrumentation stuff... >the LM324 is pretty common, as well as the LM1458 and it's cousin the >LF353 (JFET inputs). NE5532 is an audiophile part, but certainly works >as well. > >They are really easy to use; gain is set by resistors typically. Some of >them are single supply, others are dual supply. > >-- >Kris Kirby ><[EMAIL PROTECTED]>
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
On Wed, 29 Nov 2006, Bob Dengler wrote: > You can really use just about any op amp, even the old 741. For that > one the output is pin 6, not pin 1, & the V+ supply goes to pin 7 > instead of 8. I recommended the TLV2372 or LMC6482 because they're > less prone to crossover distortion. > > If you want to order the good ones: > > TLV2372: Digikey: 296-12219-5-ND $1.30 Newark: 76C7976 $1.30 Mouser: > 595-TLV2372IP $1.30 > > LMC6482: Digikey: LMC6482IN-ND $1.82 Newark: 41K2662 $1.92 Let's see.. there's a bunch of op-amps that come to mind... there's 'audiophile' amps out there, and there's just instrumentation stuff... the LM324 is pretty common, as well as the LM1458 and it's cousin the LF353 (JFET inputs). NE5532 is an audiophile part, but certainly works as well. They are really easy to use; gain is set by resistors typically. Some of them are single supply, others are dual supply. -- Kris Kirby <[EMAIL PROTECTED]>
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
At 11/29/2006 09:01 AM, you wrote: >Any chance of a source for the op amps? I called our local electronics >parts dealer and he says he is not able to cross reference them. Thanks. You can really use just about any op amp, even the old 741. For that one the output is pin 6, not pin 1, & the V+ supply goes to pin 7 instead of 8. I recommended the TLV2372 or LMC6482 because they're less prone to crossover distortion. If you want to order the good ones: TLV2372: Digikey: 296-12219-5-ND $1.30 Newark: 76C7976 $1.30 Mouser: 595-TLV2372IP $1.30 LMC6482: Digikey: LMC6482IN-ND $1.82 Newark: 41K2662 $1.92 Bob NO6B
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
Any chance of a source for the op amps? I called our local electronics parts dealer and he says he is not able to cross reference them. Thanks. Mathew [EMAIL PROTECTED] wrote: At 11/28/2006 14:52, you wrote: >Bob, I am not all that familiar with op amp's. Do you have a diagram of >something I can try to see if it works. The 1.5 KHz might be enough >allowing the controller to maintain the rest, won't know until it is all >hooked up and running. But in my thinking, 3.0 Khz would be much better, >especially for those of us that are soft spoken. > >Mathew I cut the attached out from my Portapeater keying & audio circuit; give it a try. The op amp can be just about any 8-pin dual op amp package. I prefer the TLV2372 or LMC6482. Bob NO6B - Access over 1 million songs - Yahoo! Music Unlimited.
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
At 11/28/2006 14:52, you wrote: >Bob, I am not all that familiar with op amp's. Do you have a diagram of >something I can try to see if it works. The 1.5 KHz might be enough >allowing the controller to maintain the rest, won't know until it is all >hooked up and running. But in my thinking, 3.0 Khz would be much better, >especially for those of us that are soft spoken. > >Mathew I cut the attached out from my Portapeater keying & audio circuit; give it a try. The op amp can be just about any 8-pin dual op amp package. I prefer the TLV2372 or LMC6482. Bob NO6B Image2.png Description: PNG image
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
Mathew Quaife wrote: > Bob, I am not all that familiar with op amp's. Do you have a diagram of > something I can try to see if it works. The 1.5 KHz might be enough > allowing the controller to maintain the rest, won't know until it is all > hooked up and running. But in my thinking, 3.0 Khz would be much > better, especially for those of us that are soft spoken. > > Mathew If you're eventually going into a controller but you don't have it hooked up that way yet, most controllers have PLENTY of amplification in them to handle bringing that level up, and most have a "factory recommended" way of feeding in discriminator audio (basically what Vol Sq/Hi is... it's filtered, but still pre-emphasized) and handling the 6db/octave de-emphasis. You state "The 1.5 KHz might be enough"... remember you're not looking at deviation anymore - the signal's already detected and is just a peak-to-peak AC voltage now at the point of the radio you're looking at... you just need to know if the voltage swing there at Vol Sq/Hi is "enough" for the controller's input circuits. The controller manufacturer will publish (in a good controller manual) the range that an audio input will support, and will have instructions about how to set the audio levels inside the controller and coming back out. Check the controller manual for a section that talks about how to feed the controller with (pre-)emphasized audio. That's basically what Vol Sq/Hi is, from the standpoint of most controller designs. What controller is it? If I'm mistaken about what you're trying to do here, and you're not using a commercial controller, then you'll have to come up with an amplification circuit. Here's a little (ahem...) light... reading... on op-amps, if you're so inclined. Guaranteed to cure insomnia if you struggle with that. http://focus.ti.com/lit/an/sloa058/sloa058.pdf Nate WY0X
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
Bob, I am not all that familiar with op amp's. Do you have a diagram of something I can try to see if it works. The 1.5 KHz might be enough allowing the controller to maintain the rest, won't know until it is all hooked up and running. But in my thinking, 3.0 Khz would be much better, especially for those of us that are soft spoken. Mathew Bob Dengler <[EMAIL PROTECTED]> wrote: At 11/28/2006 12:31 PM, you wrote: >I have taken a UHF transmitter and combined it with a VHF receiver for >a crossband split. The very maximum deviation that I can obtain from >the radio is about 1.5 KHz. This is with the pot turn all the way >up. Mic high is being fed into a 1.0 MFD cap through a 15K resistor >to the high side of the volume control. The audio is clear, just not >all that loud. > >Mathew I think the output Z of VOL/SQ HI is too high to use for direct feeding the MIC HI input of the G.E. TX. In addition, you need to de-emphasize the audio as the VOL/SQ HI audio is still pre-emphasized & the TX audio is also pre-emphasized again. This means you need a buffer (op)amp to de-emphasize the audio & drive the 600 ohm mic input. Bob NO6B - Everyone is raving about the all-new Yahoo! Mail beta.
Re: [Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
At 11/28/2006 12:31 PM, you wrote: >I have taken a UHF transmitter and combined it with a VHF receiver for >a crossband split. The very maximum deviation that I can obtain from >the radio is about 1.5 KHz. This is with the pot turn all the way >up. Mic high is being fed into a 1.0 MFD cap through a 15K resistor >to the high side of the volume control. The audio is clear, just not >all that loud. > >Mathew I think the output Z of VOL/SQ HI is too high to use for direct feeding the MIC HI input of the G.E. TX. In addition, you need to de-emphasize the audio as the VOL/SQ HI audio is still pre-emphasized & the TX audio is also pre-emphasized again. This means you need a buffer (op)amp to de-emphasize the audio & drive the 600 ohm mic input. Bob NO6B
[Repeater-Builder] GE Exec II Conv. Max audio 1.5 KHz Dev, how can I increase it
I have taken a UHF transmitter and combined it with a VHF receiver for a crossband split. The very maximum deviation that I can obtain from the radio is about 1.5 KHz. This is with the pot turn all the way up. Mic high is being fed into a 1.0 MFD cap through a 15K resistor to the high side of the volume control. The audio is clear, just not all that loud. Mathew
