odd Pro197 behavior...

[rjvalenta]

on my roof are 4 antenna...

a 4010 EFHW and a 10m/6m/2m/70cm vertical, attached to my IC7100

a dual band 2m/70cm, attached to my FTM400.

and a tram 1411 discone for my Pro197

they are all at least 8ft apart.

the base of the discone mast is a few feet lower on the roof than the rest which are at the peak, but it's so tall with the cb top whip that it reaches higher than the 2m/70cm for the FTM400 and the balun of the EFHW. but - the discone is easily the closest to the EFHW. 8ft away in the direct opposite direction as the wire, and the disc just below the balun.

so then i get my General ticket and i've been rolling through the bands on FT8 for the last 3 weeks, usually at 75w or more if i'm going for someone far away.

and when i'm not, sometimes i'll have WSPR running, which does spill in to 2m/70cm if you're rotating through all the bands, which i was... though usually have WSPR at a lower wattage.

so now i'm sitting here looking at my Pro197 and my FTM400 - the FTM400 is hearing a conversation on a local ham repeater on 146.850, the Pro197 is not.

but, if i hit WX the Pro197 picks up 162.550 instantly and clearly.

none of my 146Mhz channels are coming in...

so i reset the radio and manually add the 146.85Mhz repeater... still nothing... turn the squelch to nothing, wide open - it hears nothing - the FTM400 still hearing the conversation.

then i use Win500 to reload all my channels - instantly getting 800Mhz local trunked channels and 461Mhz conventional channels.

earlier i was hearing 6m traffic, made me wonder, so i picked up my CB and transmit on ch6 - picks it up loud and clear...

the FTM400 is hearing the local ham repeaters, my Anytone handheld is hearing local repeaters... but... not the Pro197.

so i'm picking up 27.025Mhz, 52Mhz, 162.550Mhz, 461Mhz, 800Mhz... but... it can't hear 146Mhz or anything in the 2m ham band.

WHY??

and really, I'm wondering if somehow I damaged the scanner with WSPR... but that's a max of 50w from 10ft away, so... not likely, right? possibly damage from FT8... but... would 100w of HF data screw up the receive of 2m traffic, and only 2m ham traffic?

it's an old scanner, if it's just age and wear, then so be it - it's been a great scanner - an amazing scanner - and aside from 2m ham still is.... but i'd like to figure out why. my concern is that somehow i caused this with other RF traffic. and i'd hate to save and plan and shell out for something like an SDS200 some day, only to cause it the same damage.

anyone have any ideas on how to test it or what could be the cause?

thanks & 73,

Richard
N0TZC

 

[tvengr]

Please attach your programming file so that we can take a look at it. You will need to right click on the file and Send to Compressed (zipped) folder to be able to attach it. Click on Attach files and open the zipped folder. What is your city, county, and state?

 

[rjvalenta]

Please attach your programming file so that we can take a look at it. You will need to right click on the file and Send to Compressed (zipped) folder to be able to attach it. Click on Attach files and open the zipped folder. What is your city, county, and state?

please find the attached file

 

[rjvalenta]

ALSO -

i can transmit from the VFO on my Anytone 878 handheld in analog and the scanner hears it fine on 146.52 and 146.85 - but it does not hear any of the local repeaters at all.

and i did just hear it pick up LEO Point to Point on 158Mhz, was very very static laden, but they could have been a far away station.

thanks again.

 

[tvengr]

Are you receiving 146.85 on scan list 1 or 19? Most of the conventional frequencies have the attenuator on. That will greatly decrease the range.

 

[rjvalenta]

Are you receiving 146.85 on scan list 1 or 19? Most of the conventional frequencies have the attenuator on. That will greatly decrease the range.

I'm not receiving 146.85 anywhere unless it's from the handheld actually at my house, with the attenuator on everything worked fine until recently. scanlist 19 was created in an attempt to have the most recently downloaded VHF ham info to make sure i didn't screw something up somewhere.

 

[tvengr]

Is scan list 1 disabled while scanning scan list 19?

 

[rjvalenta]

no i just have them rolling through the two lists, one with attenuation, one with no att and unmodified from RR download.

 

[tvengr]

Go to the General Settings tab in Win500. Under Miscellaneous Settings, remove the check mark from TGRPs in disabled SLs = Locked Out. Upload to Scanner again. Since 146.85 is included in scan list 1, it will be locked out in scan list 19 if scan list 1 is disabled. Scan only scan list 19 and see what happens.

 

[rjvalenta]

Go to the General Settings tab in Win500. Under Miscellaneous Settings, remove the check mark from TGRPs in disabled SLs = Locked Out. Upload to Scanner again. Since 146.85 is included in scan list 1, it will be locked out in scan list 19 if scan list 1 is disabled. Scan only scan list 19 and see what happens.

i did this and only scanned group 19... i can key up the scanner from my handheld, but it does not hear the repeater while my FTM400 does.

first i tried 146.85 in the handheld VFO, scanner picked me up instantly... then i went to the repeater in memory on the handheld, kerchunked it, could barely hear it reply on the handheld but could hear it reply on the FTM400 that has it's antenna outside... nothing on the scanner.

just to check everything, i then connected the handheld to the coax coming from the discone, it worked as it should transmit and receive.

hooked the coax back to the scanner and tried that all again with the 146.91 repeater, same, handheld could hear the repeater respond, FTM400 heard it respond, Pro197 didn't even notice - but does when i send a low power VFO transmission from my handheld.

it's almost like the scanner is ignoring repeaters... or just ignoring the 2m ham band, ha. i dunno, i'm at a loss, but i'm willing to try any other ideas you have.

 

[tvengr]

It isn't unusual for the receiver to be overloaded when transmitting at high power on a nearby transmitter. It is probably blanking the repeater output frequency when you key up the handheld. Program the 197 with the repeater input frequency in scan list 19 and then key up your handheld. I bet you will hear it. It should also work if you set your 197 to the repeater output frequency and then transmit on the repeater output frequency with your handheld.

 

[rjvalenta]

It isn't unusual for the receiver to be overloaded when transmitting at high power on a nearby transmitter. It is probably blanking the repeater output frequency when you key up the handheld. Program the 197 with the repeater input frequency in scan list 19 and then key up your handheld. I bet you will hear it. It should also work if you set your 197 to the repeater output frequency and then transmit on the repeater output frequency with your handheld.

right... but the problem is that my HF isn't transmitting all the time... nothing is... when i noticed the problem i stopped all transmissions to make sure there wasn't any interference. and thats the worst part - the scanner always hears my handheld, it hears 2w from close by but can't hear the 100w from the repeater that's 3 miles away on top of a building.

 

[tvengr]

Did you have the attenuator applied on 146.85 in scan list 1 when it stopped working? Is there a new NOAA weather transmitter, FM broadcast station, TV station, or cell phone tower near you? Did a TV station recently change frequencies? Did you recently install a new USB adapter?

 

[rjvalenta]

Did you have the attenuator applied on 146.85 in scan list 1 when it stopped working? Is there a new NOAA weather transmitter, FM broadcast station, TV station, or cell phone tower near you? Did a TV station recently change frequencies? Did you recently install a new USB adapter?

i have always had the attenuators on... i am in the city center, most radio/tv transmitters are roughly 5mi south of me, NOAA is about 10m west of me. what you see in scanlist 1 is how things have always been set up, scanlist 19 is the open, no CTCSS, please react to 146Mhz version.

that's the weird thing... why have no problems everywhere else, why hear 158Mhz, or 28Mhz, or 461Mhz, or 52Mhz, or NOAA at 162.550... but... just can't hear 146Mhz?

 

[tvengr]

If you take the scanner outside and run it on battery power, do you still have problems. There could be some interfering source in your or your neighbor's residence in that frequency range only. Does the scanner work in your car? Appliances, radios, TV's, computers, USB adapters, and wall warts with switching power supplies can all radiate signals and cause interference. It would be worth the effort to run your scanner on battery power and kill the master circuit breaker in your residence to see if the problem goes away.

 

[rjvalenta]

If you take the scanner outside and run it on battery power, do you still have problems. There could be some interfering source in your or your neighbor's residence in that frequency range only. Does the scanner work in your car? Appliances, radios, TV's, computers, USB adapters, and wall warts with switching power supplies can all radiate signals and cause interference. It would be worth the effort to run your scanner on battery power and kill the master circuit breaker in your residence to see if the problem goes away.

i'm certainly willing to try this and will try to make time to do all this over the weekend... but why would the other radios receive from the same location and even same antenna but not the Pro197 if it's RFI? wouldn't everything have interference?

 

[tvengr]

Your various radios probably use a different IF. Local oscillators can operate above or below the incoming frequency. Scanners need to scan a very wide range of frequencies. They frequently have image frequency problems. I could set my old Bearcat 210 scanner to 38.16 MHz and monitor Channel 2 TV audio on 59.76 MHz. The scanner used a 10.8 MHz first IF. The local oscillator operated at 48.96 MHz to receive 38.16 MHz (48.96-38.16=10.8). The image frequency for 38.16MHz on that particular scanner is 59.76 MHz (59.76-48.96=10.8 also). Either frequency will feed through the first IF. Radios built for a specific range of frequencies are built to minimize interference within the range they are using. With the recent repacking of the UHF TV channels, many stations have changed frequencies. The repacking has also resulted in many VHF channels changing frequencies. Even though a TV station may be 5 miles away, it is a high power transmitter. TV channels are 6 MHz wide. Beating against the local oscillator can cause a wide range of interference. Did you recently have to rescan your TV due to frequency changes?

 

[db_gain]

"that's the weird thing... why have no problems everywhere else, why hear 158Mhz, or 28Mhz, or 461Mhz, or 52Mhz, or NOAA at 162.550... but... just can't hear 146Mhz?"

Dunno where the cutoff is for the HAM 2m band as far as bandpass goes in the 197, but if you fried and input diode in the input bandpass for 2m that would explain why 2m is dead. Most scanners will have some form of hardware tuned bandpass in the input that allows only the band of interest as it scans, greatly diminishing the strength of sigs outside the bandpass.
Say you tune to 28mHz, the scanner selects the bandpass that covers 28MHz to allow you to hear only the signal of interest, likely one that allows 25 to 88MHz to hit the front end of the scanner, scan 120MHz and it selects the 120MHz bandpass, and so on.
See here for more;

RF and AF Filters

The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources.

www.arrl.org

If you fried a passband diode the diode will have to be replaced to restore sensitivity to that range. I was wondering if there was a bandpass for the 2m band and it looks like there may be, as on page 85 of the manual it says 144.0 to 147.995, if that is a hardware bandpass you might have fried it with too much rf getting into it. I supect many scanners can tolerate up to maybe 10w from a nearby v/uhf transmitter, but 50watts might be pushing it.

 

[rjvalenta]

"that's the weird thing... why have no problems everywhere else, why hear 158Mhz, or 28Mhz, or 461Mhz, or 52Mhz, or NOAA at 162.550... but... just can't hear 146Mhz?"

Dunno where the cutoff is for the HAM 2m band as far as bandpass goes in the 197, but if you fried and input diode in the input bandpass for 2m that would explain why 2m is dead. Most scanners will have some form of hardware tuned bandpass in the input that allows only the band of interest as it scans, greatly diminishing the strength of sigs outside the bandpass.
Say you tune to 28mHz, the scanner selects the bandpass that covers 28MHz to allow you to hear only the signal of interest, likely one that allows 25 to 88MHz to hit the front end of the scanner, scan 120MHz and it selects the 120MHz bandpass, and so on.
See here for more;

RF and AF Filters

The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources.

www.arrl.org

If you fried a passband diode the diode will have to be replaced to restore sensitivity to that range. I was wondering if there was a bandpass for the 2m band and it looks like there may be, as on page 85 of the manual it says 144.0 to 147.995, if that is a hardware bandpass you might have fried it with too much rf getting into it. I supect many scanners can tolerate up to maybe 10w from a nearby v/uhf transmitter, but 50watts might be pushing it.

so... if i replace the scanner and put zero 2m ham frequencies in the new one - will i still risk frying that part when i'm scanning other bands?

or did i do this unit in by transmitting 50w from 8ft away while it listened on the same band?

 

[tvengr]

How well does aircraft monitoring work? Unfortunately, I don't have a schematic for the scanner. If it does use diodes for band selection, a high RF level is not going to fry a band selection diode where it is located in the circuit. Some scanners use varactor diodes (variable capacitance controlled by voltage) to adjust RF tuning. It is possible a bad varactor could cause low sensitivity at the low end of the VHF band. The control voltage applied to a varactor is adjusted depending upon the frequency being received which would be a function of the firmware. What firmware version do you have in the scanner? The latest CPU (uP) firmware is v2.1 and the latest DSP firmware is v1.4. It wouldn't hurt to reload the CPU firmware even if it is the latest version. To determine the firmware versions in your scanner: Turn off the scanner. Turn on the scanner. At the welcome screen, press 3.