Re: [Repeater-Builder] GLB Preselector
I'm assuming you mean preselector - preamp. At that frequency, they were usually made with a bipolar transistor, unless it was custom made; then it could be a GaAs device. It is a MRF-901 (or equivalent) if it is bipolar. Many times only 901 appeared on the device, if it wasn't ever changed. Looking at the components around it, one should be able to tell if it's a FET or a regular transistor. I never owned one with a FET device, so I don't know what that would be. Kevin ldgelectronics wrote: Anyone know the device number of the gaasfet (or whatever type it is) in the P-145 model? Inherited one with -12 db gain. Looks easy enough to fix. Thanks, Dwayne Kincaid WD8OYG
Re: [Repeater-Builder] GLB Preselector
At 03:49 AM 12/28/07, you wrote: Anyone know the device number of the gaasfet (or whatever type it is) in the P-145 model? Inherited one with -12 db gain. Looks easy enough to fix. Thanks, Dwayne Kincaid WD8OYG I fixed one years ago with a Siliconix U-310, but I have no doubt that there are better devices out there today. Mike WA6ILQ
Re: [Repeater-Builder] GLB Preselector
I have a GLB Model P-147.49 that was custom made for me years ago. It use an MRF901 device. 73, Joe, K1ike ldgelectronics wrote: Anyone know the device number of the gaasfet (or whatever type it is) in the P-145 model? Inherited one with -12 db gain. Looks easy enough to fix. Thanks, Dwayne Kincaid WD8OYG
Re: [Repeater-Builder] GLB Preselector Preamp, Re: midland 13-509 220mhz to convert to repeater
The GLB worked very well on my FM-76 (aka 13-509) but it only gave about 8dB gain overall to the receiver. Most of the gain was lost in the helical coil front end, but it worked wonders on marginal receivers. It tighten up the receiver and gave the impression of more added gain than 8dB. I still have a couple around for 222Mhz, maybe I'll sell them if there is an interest. 73, Joe, k1ike At 05:28 PM 8/3/2005 -0400, you wrote: For Years I used the GLB Preamp/Preselector on thefront end of my Midland 509 220Mhz repeater the preamp stage is an MRF-901 I think a Gasfet Preamp will create to much noise Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] GLB Preselector
I move them a little at a time, don't try to make big changes or you will not be able to get a signal through it. If you want to, you can take the cover off and inject a signal into each stage. Work from the output towards the antenna connection. When you are able to get a signal from input to output that you can measure, put the cover back on and do the final tune up. 73, Joe, K1ike At 07:42 PM 8/4/2005 +, you wrote: Anybody know the proper tuning procedure to peak up/ move freq for the GLB preamp/preselector to maintain the rated selectivey? Dale K0JXI Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] GLB Preselector Preamp, Re: midland 13-509 220mhz to convert to repeater
At 8/2/2005 06:55 PM, you wrote: Joe wrote: I had an FM76 convered to a 220Mhz repeater and used a GLB preselector in front of the receiver. It helped a lot. Unfortunately, the GLB is no longer available. Are you sure? http://www.aria-glb.com/products/reset_frames.htm?/products/preselector.htm Kevin Anyone measure the noise figure of one of these units? Even with the GaAsFET preamp, the overall NF is going to be high if the helical resonator loss is too high (resistive loss = NF). Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] GLB Preselector Preamp, Re: midland 13-509 220mhz to convert to repeater
For Years I used the GLB Preamp/Preselector on thefront end of my Midland 509 220Mhz repeater the preamp stage is an MRF-901 I think a Gasfet Preamp will create to much noise Bob Dengler wrote: At 8/2/2005 06:55 PM, you wrote: Joe wrote: I had an FM76 convered to a 220Mhz repeater and used a GLB preselector in front of the receiver. It helped a lot. Unfortunately, the GLB is no longer available. Are you sure? http://www.aria-glb.com/products/reset_frames.htm?/products/preselector.htm Kevin Anyone measure the noise figure of one of these units? Even with the GaAsFET preamp, the overall NF is going to be high if the helical resonator loss is too high (resistive loss = NF). Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] GLB Preselector Preamp, Re: midland 13-509 220mhz to convert to repeater
Bob Dengler wrote: At 8/2/2005 06:55 PM, you wrote: Joe wrote: I had an FM76 convered to a 220Mhz repeater and used a GLB preselector in front of the receiver. It helped a lot. Unfortunately, the GLB is no longer available. Are you sure? http://www.aria-glb.com/products/reset_frames.htm?/products/preselector.htm Kevin Anyone measure the noise figure of one of these units? Even with the GaAsFET preamp, the overall NF is going to be high if the helical resonator loss is too high (resistive loss = NF). Bob NO6B While I have never measured it, I can tell you the noise figure is higher than a stock Hamtronics receiver with GaAs Fet's. Of course, this unit should be used to filter out of band signals on receivers that don't include a good front end filter, not as a preamp. The preamp is only there to recover some of the loss of the unit, not to add sensitivity. If the receiver is already good, this preselector/preamp *can* make it worse, but, I'd bet it would add usable sensitivity to a Mastr Pro type receiver with a basic sensitivity of .5 uV. I have found that the resulting sensitivity is slightly better than a good Micor or Mastr II (without a preamp) with this P/P combination added to an already decent receiver (Hamtronics R100, or the like). On VHF (including 220) , I have found nothing that beats a good Micor RX with its companion helical preamp. Kevin YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] GLB Preselector Preamp, Re: midland 13-509 220mhz to convert to repeater
I think you are confused Neal, the GaAs FET option was available on GLB P/P 200 MHz and above. I did have them build me one for 2 meters, but I didn't see much difference in the performance over the MRF-901 on 2 meters; certainly not worth the added cost. Kevin Neal Newman wrote: For Years I used the GLB Preamp/Preselector on thefront end of my Midland 509 220Mhz repeater the preamp stage is an MRF-901 I think a Gasfet Preamp will create to much noise Bob Dengler wrote: At 8/2/2005 06:55 PM, you wrote: Joe wrote: I had an FM76 convered to a 220Mhz repeater and used a GLB preselector in front of the receiver. It helped a lot. Unfortunately, the GLB is no longer available. Are you sure? http://www.aria-glb.com/products/reset_frames.htm?/products/preselector.htm Kevin Anyone measure the noise figure of one of these units? Even with the GaAsFET preamp, the overall NF is going to be high if the helical resonator loss is too high (resistive loss = NF). Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] GLB Preselector Preamp, Re: midland 13-509 220mhz to convert to repeater
Joe wrote: I had an FM76 convered to a 220Mhz repeater and used a GLB preselector in front of the receiver. It helped a lot. Unfortunately, the GLB is no longer available. Are you sure? http://www.aria-glb.com/products/reset_frames.htm?/products/preselector.htm Kevin Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
