| Author |
Message |
    
Radioreddz
Junior Member
Username: Radioreddz
Post Number: 11
Registered: 9-2006
| | Posted on Monday, November 27, 2006 - 4:42 pm: | 
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have a trc 458 talks loud but my ears are weak, is there an adjustment to be made by made turning a pot. seems like the ears need to be brought up sum |
Hotwire
Senior Member
Username: Hotwire
Post Number: 2071
Registered: 1-2005
| | Posted on Tuesday, November 28, 2006 - 3:03 pm: |
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Radioreddz, You may want to check your coax and antenna. Maybe get a better antenna and fresh coax? They are the 2 most important componets to good recieve. Sometimes a preamp helps.
kenny
cef491 |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2319
Registered: 9-2004
| | Posted on Tuesday, November 28, 2006 - 6:46 pm: |
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very hard to tell if your radio isnt receiving well enough unless you have something to reference it against.
is evryone suddenly hitting you with alot less S-units?
does it just seem like there is no one out there?
how did you notice this "phenomenon"?
i agree with kenny about the antenna and coax.
best to make sure both are in tip top shape.
give up some details about why you think the radio is out of adjustment.
matt |
Radioreddz
Junior Member
Username: Radioreddz
Post Number: 12
Registered: 9-2006
| | Posted on Wednesday, November 29, 2006 - 12:28 am: |
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hey guys thanks for the respons, and yup i do have other radios to reference the lack of receive. i can have a cobra 2000 or dak in line and i might have 7 or 8 s units on another station and on the trc 458 it might be only 2 or 3 and the signal is weak so i know i don't have a stingy needle. or i can hear others talking to stations in the distance on the other radios i have i might barely hear them but with the trc 458 i might not hear them at all. thats how i figured i had problem with my ears. i know some techs use a signal generater to peak up the ears can this be done by turning a pot while listing to a distant station to bring in the receive stronger. |
Hotwire
Senior Member
Username: Hotwire
Post Number: 2076
Registered: 1-2005
| | Posted on Wednesday, November 29, 2006 - 12:02 pm: |
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Radioreddz,Yes,but it is more than one pot to turn. When a tech connects your radio to his hi qaulity gear for an alighnment this is what he is doing very carefully while watching his displays. Tuning one of those cans by ear could cause more problems.
Most likely it needs an alighnment. If you have had the radio alighned in the past and your recieve used to be better it might be something different, like a radio getting old and ready to go on the vintage shelf. Also comparing the recieve of the Realistic to the Cobra 2000 is not fair to the Realistic!
Sorry but I don't know the location of the adjustments in that radio. I know its hard to find a tech to do work on a base. A good sidebander tech is even harder to find!
Sorry I can't help you any.
kenny |
Yankee
Senior Member
Username: Yankee
Post Number: 1372
Registered: 7-2003
| | Posted on Wednesday, November 29, 2006 - 6:43 pm: |
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Had a few of these uPD-858 PLL radios when they first came on the market in the late 1970s.
I would first start with a good cleaning of the relay, with a good grade electronic parts cleaner spray, ((not TV tuner cleaner)). Then if this doesn't fix the problem, I would venture to say yes that an alignment might be the answer. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2324
Registered: 9-2004
| | Posted on Wednesday, November 29, 2006 - 7:41 pm: |
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what is the history of the radio?
did it used to work fine for you and now doesnt?
or is this a new addition to the shack with an unknown past?
the problem is; this radio is quite old by now, and when they get old, weird problems tend to rear their ugly heads, and the causes can be hard to track down.
could be a weak or dead electrolytic capacitor. they do dry out over time. look under the top cover of the radio. do you see a big hot spot right where the transfomer would be if the cover was on the radio?
this is a good indication that the radio has seen alot of use and has been on for hours at a time.
its a good candidate to have all the electrolytics replaced.
and go ahead and replace C179 with a 2.2uF electroytic cap. it will go bad eventually. should have been an electrolytic from the factory.
if you have the correct plastic tuning tools, and you want to try aligning the receive, here is how to do it: (if you dont have the proper tool, you will crack the ferrite slug and render the radio useless)
put the radio on ch.20. ANL off, NB off, squelch all the way CCW,clarifier centered, AM mode.
turn the volume up so you can hear it well.
make sure there is no signal coming in on the radio, as you need a constant noise level to tune with.
adjust these coils in this order, for maximum noise from the speaker and maximum S meter reading.
adjust very slowly, and carefully. if there is any wax or glue on any of the coils, leave them alone.
adjust L3,4,5,6,7, and L8.
go back and check for even sensitivity on ch.1 and 40. if one is very clearly less sensitive, go back to the coil that is two coils in one can (L4&5 i think) and slightly tune it on ch. 1 and 40 until you get an even balance.
good luck,
matt |
Radioreddz
Junior Member
Username: Radioreddz
Post Number: 13
Registered: 9-2006
| | Posted on Thursday, November 30, 2006 - 12:11 am: |
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thanks guys i guese i will leave this up to my tech guy to do. will try the alignmnet. i am real lucky to have a very very good honest tech in the virginia area great with the tube and solid state radios |
Bruce
Senior Member
Username: Bruce
Post Number: 4199
Registered: 9-2003
| | Posted on Thursday, November 30, 2006 - 8:59 am: |
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There is no good way to check a receiver with out a generator .......
"S" meters are next to worthless good example is the meter on the TS-2000 it takes a moble parked in front of the house to peg it while a IC-706 bar meters is a easy peg.
when the guy fixes it have him measure it's noise floor I would be interested to know just how good it comes out. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 2330
Registered: 9-2004
| | Posted on Thursday, November 30, 2006 - 11:31 pm: |
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if you're going to take it to the tech, i would recommend you not mess with aligning the coils beforehand.
just let him figure it out.
good luck,
matt |
