Yaesu FT221 2 meter all mode Transceiver. Some observations and a small
technical problem solved (one of the crystals stopped oscillating).
technical problem solved (one of the crystals stopped oscillating).
hamelectronicsmagazine.com March 10, 2011
I have owned 2 FT221s. The period of ownership spans about 15 years and this is really the first failure I have had. I turned on the set and tried to listen
down around the SSB/CW band..144.200 plus or minus and tune around..but the radio was dead. All the other band segments were fine. There are 8 band
segments for full 4 MHZ coverage of the 2 meter amateur band. I suspected right away a dead crystal.
Since about 2005, I have been selling spare parts for these older solid state transceivers and ham equipment. My biggest inventory of spare boards and
parts is for the FT301 series. I have bought 2 junker units that were in bad shape and I have been pulling parts from them for both my own spares and to sell
to others. Crystals are a common problem. They seem to be dying out now! The FT301 and FT221 date back to the late 70s and mid 80s. In that era..and I'm not
sure of the exact dates or anything. I guess crystals just go bad with time! The 10 meter (42.5 mhz) seems to be the most common crystal request I have had.
So much so, that I have ordered a couple from BRY Brian Carling AF4K. to replenish my stocks.
Anyways..back to the FT221. It has plug in circuit boards and it wasn't hard to open up the cabinet and pull the card with all the crystals on it. I used a bit of
solder flux to help the solder flow better and using my trusty old radio shack desoldering tool..I removed the crystal.
Next..I tested the crystal in my very simple TTL oscillator circuit. Clip leads and point to point wiring on a circuit board dead bug style..this little oscillator has
served me very well. The crystal worked in my test oscillator! So ..I guess the crystal is still good. Perhaps just the heat from desoldering brought it back to
life??? I have heard someone mention on the radio..a type of thermal shock treatment for treating crystals. CAUTION: dont use too much heat. I took my
black and decker heat gun to a small surplus crystal and I melted the solder of the case and then I removed the case to find the crystal had fractured! -- YOu
can use this to good advantage to take scrap crystals apart if you have some purpose in mind.
Well..the crystal is oscillating in my NAND gate test circuit. You can see the harmonics on the spectrum analyser. This is normal. No filter in my test circuit. So
I plug it back in to the board and solder it down and put the board back into the rig..and presto!! The 144 mhz to 144.5 mhz band segment is once again alive.
down around the SSB/CW band..144.200 plus or minus and tune around..but the radio was dead. All the other band segments were fine. There are 8 band
segments for full 4 MHZ coverage of the 2 meter amateur band. I suspected right away a dead crystal.
Since about 2005, I have been selling spare parts for these older solid state transceivers and ham equipment. My biggest inventory of spare boards and
parts is for the FT301 series. I have bought 2 junker units that were in bad shape and I have been pulling parts from them for both my own spares and to sell
to others. Crystals are a common problem. They seem to be dying out now! The FT301 and FT221 date back to the late 70s and mid 80s. In that era..and I'm not
sure of the exact dates or anything. I guess crystals just go bad with time! The 10 meter (42.5 mhz) seems to be the most common crystal request I have had.
So much so, that I have ordered a couple from BRY Brian Carling AF4K. to replenish my stocks.
Anyways..back to the FT221. It has plug in circuit boards and it wasn't hard to open up the cabinet and pull the card with all the crystals on it. I used a bit of
solder flux to help the solder flow better and using my trusty old radio shack desoldering tool..I removed the crystal.
Next..I tested the crystal in my very simple TTL oscillator circuit. Clip leads and point to point wiring on a circuit board dead bug style..this little oscillator has
served me very well. The crystal worked in my test oscillator! So ..I guess the crystal is still good. Perhaps just the heat from desoldering brought it back to
life??? I have heard someone mention on the radio..a type of thermal shock treatment for treating crystals. CAUTION: dont use too much heat. I took my
black and decker heat gun to a small surplus crystal and I melted the solder of the case and then I removed the case to find the crystal had fractured! -- YOu
can use this to good advantage to take scrap crystals apart if you have some purpose in mind.
Well..the crystal is oscillating in my NAND gate test circuit. You can see the harmonics on the spectrum analyser. This is normal. No filter in my test circuit. So
I plug it back in to the board and solder it down and put the board back into the rig..and presto!! The 144 mhz to 144.5 mhz band segment is once again alive.
Crystal Problems and Solutions
and discussions
and discussions
With the FT301 (very similar type of circuitry) and it looks the same as well: I have had a problem with crystals stopping their oscillating function. Sometimes you
can touch up the associated trimmer capacitor and the oscillation will start again. Or do like I did with the FT221 and remove with heat then resolder. Either the
heat might perk up the crystal or perhaps it was a cold solder joint. I have done several repairs now on FT301s that have had bad solder joints. YOu would think
that after the 30 years they have been around that any of these bugs would have long since reared their ugly heads but they seem to continue to crop up every
now and again!
can touch up the associated trimmer capacitor and the oscillation will start again. Or do like I did with the FT221 and remove with heat then resolder. Either the
heat might perk up the crystal or perhaps it was a cold solder joint. I have done several repairs now on FT301s that have had bad solder joints. YOu would think
that after the 30 years they have been around that any of these bugs would have long since reared their ugly heads but they seem to continue to crop up every
now and again!
Dial Lamp replacement. MODERN L.E.D.s (very bright L.E.D.s) with low
power consumption..are a possible substitute for incandescent bulbs.
power consumption..are a possible substitute for incandescent bulbs.
I did a screen snapshot of this FT221 from a YOU TUBE
MOVIE. Notice the blueish looking background lighting.
I suspect..this fellow has used some bright white LEDs
to backlight the display and meter.
I did try one LED with a box in the dark and it did not
seem to throw enough light..(at least not without a
reflector perhaps). Also the light is a blueish color.
I forget the size of resistor I had to use to limit the
current. Perhaps it was in the 5kilohm to 10 kilohm
range.
I can see using a number of these bright LEDs with
perhaps a potentiometer and limiting resistor in order
to create a background light for the front panel.
I was surprised that YOU TUBE has so many little movie
clips and instructional videos on using the old FT301
and the FT221. They are still fairly popular.
MOVIE. Notice the blueish looking background lighting.
I suspect..this fellow has used some bright white LEDs
to backlight the display and meter.
I did try one LED with a box in the dark and it did not
seem to throw enough light..(at least not without a
reflector perhaps). Also the light is a blueish color.
I forget the size of resistor I had to use to limit the
current. Perhaps it was in the 5kilohm to 10 kilohm
range.
I can see using a number of these bright LEDs with
perhaps a potentiometer and limiting resistor in order
to create a background light for the front panel.
I was surprised that YOU TUBE has so many little movie
clips and instructional videos on using the old FT301
and the FT221. They are still fairly popular.
I briefly tried some bright LEDs but I found one on its
own did not throw enough light to light up my S meter.
I went into the junkbox and found a lamp and used
electrical tape to form a thick enough diameter bulb to
fit in the holding grommit. Maybe down the road..I will
try the LEDs next time my radio lamps burn out.
own did not throw enough light to light up my S meter.
I went into the junkbox and found a lamp and used
electrical tape to form a thick enough diameter bulb to
fit in the holding grommit. Maybe down the road..I will
try the LEDs next time my radio lamps burn out.
This article is still being written. This magazine..hamelectronicsmagazine.com is
in its infancy. It was just started here in March 2011. I will be writing articles
almost daily for it. Advertisers will be welcome to put small ads on this site.
Most of the articles from my old site (www.earlandrews.com) will be re-written
and condensed a bit perhaps and will appear on this site. This will take a
number of months. 73 for now..Earl VE3AB March 12, 2011.
in its infancy. It was just started here in March 2011. I will be writing articles
almost daily for it. Advertisers will be welcome to put small ads on this site.
Most of the articles from my old site (www.earlandrews.com) will be re-written
and condensed a bit perhaps and will appear on this site. This will take a
number of months. 73 for now..Earl VE3AB March 12, 2011.
Above: I tried a single one of these newer "bright" white LEDs and I found it did not throw
enough light for my liking. To the right: and also pictured above: I found a 12 volt bulb from an
older radio and it worked much better. I won't be giving up the idea of using LEDs as
alternatives to incandescent bulbs. I think maybe two or three of them together might throw
enough light. The current draw would still likely be much less than a standard bulb and the
lifetime of the LED is likely much greater if you dont push them too hard.
enough light for my liking. To the right: and also pictured above: I found a 12 volt bulb from an
older radio and it worked much better. I won't be giving up the idea of using LEDs as
alternatives to incandescent bulbs. I think maybe two or three of them together might throw
enough light. The current draw would still likely be much less than a standard bulb and the
lifetime of the LED is likely much greater if you dont push them too hard.
Above: I used some white electrical tape to fatten up the bulb
at the base so that it would fit snugly in the rubber holder. Its
not pretty but it works. A string of LEDS perhaps green or
yellow to backlight the S meter and/or dial might be more
pleasing to the eye. Perhaps some sort of fiberglass strip cut to
fit in the holder and support the LEDs.
at the base so that it would fit snugly in the rubber holder. Its
not pretty but it works. A string of LEDS perhaps green or
yellow to backlight the S meter and/or dial might be more
pleasing to the eye. Perhaps some sort of fiberglass strip cut to
fit in the holder and support the LEDs.
Snooping around with google I found a link to how to use LEDs
as dial lamps..here is one link:
http://www.irebuildmarantz.com/leds/lamps.html
as dial lamps..here is one link:
http://www.irebuildmarantz.com/leds/lamps.html
http://www.irebuildmarantz.com/leds/lamps.html
web site above shows how one fellow does it. He uses a dremel tool and sanding drum to take down the top "lens" of the LED and to roughen the surface of the LED
plastic in order to create a diffused light. He uses 1/4 watt resistors between 56 and 270 ohms. NOTE: it doesnt take long to burn out one of these LEDs!! I did it when
fooling around with resistor values! You will see a wee bit of smoke then its too late! It is a comprimise of resistance value with brightness vs. longevity.
I will likely do more work at this but now..I have many projects on the bench and this magazine to write..so I will have to move on to more pressing things. I'm sure with
google searches and perhaps using YAHOO groups ect..you can come up with many more good ideas and practices.
web site above shows how one fellow does it. He uses a dremel tool and sanding drum to take down the top "lens" of the LED and to roughen the surface of the LED
plastic in order to create a diffused light. He uses 1/4 watt resistors between 56 and 270 ohms. NOTE: it doesnt take long to burn out one of these LEDs!! I did it when
fooling around with resistor values! You will see a wee bit of smoke then its too late! It is a comprimise of resistance value with brightness vs. longevity.
I will likely do more work at this but now..I have many projects on the bench and this magazine to write..so I will have to move on to more pressing things. I'm sure with
google searches and perhaps using YAHOO groups ect..you can come up with many more good ideas and practices.
I found an interesting article by Phil AD5A called "solid state those pilot lamps". I found it on the Yahoo Group Amateur Radio Repairs. Those Yahoo Groups
have good files and information, photos and cross references for parts and sources for parts. The Yahoo Ft301 has 2 groups. Other radios have groups
dedicated to them such as FT101, TS-780 and much more. Phils article is a 3 page pdf file with photos. He details how the new ultra bright LEDs draw about
20 milliamps. He determined, with 6.3 vac (pilot lamp voltage in older tube rigs) that the following resistors will work: White 82 ohms, Green, Amber, Blue :
100 ohms and red 120 ohms. The FT221 radio has 12 or 13 volt bulbs/lamps. What he did was use a 500 ohm pot to set the current and then use a fixed
resistor. He used old burned out bulbs and hollowed out the glass and rebuilt the bulb with an LED. The led has to be facing the front of the rig for the light
to be effective. I have seen other people who used a file to roughen up the surface of the LED. That spreads out the light. I'm sure there are quite a few
articles out there to be googled regarding this subject.
have good files and information, photos and cross references for parts and sources for parts. The Yahoo Ft301 has 2 groups. Other radios have groups
dedicated to them such as FT101, TS-780 and much more. Phils article is a 3 page pdf file with photos. He details how the new ultra bright LEDs draw about
20 milliamps. He determined, with 6.3 vac (pilot lamp voltage in older tube rigs) that the following resistors will work: White 82 ohms, Green, Amber, Blue :
100 ohms and red 120 ohms. The FT221 radio has 12 or 13 volt bulbs/lamps. What he did was use a 500 ohm pot to set the current and then use a fixed
resistor. He used old burned out bulbs and hollowed out the glass and rebuilt the bulb with an LED. The led has to be facing the front of the rig for the light
to be effective. I have seen other people who used a file to roughen up the surface of the LED. That spreads out the light. I'm sure there are quite a few
articles out there to be googled regarding this subject.
link back to main index page of
hamelectronicsmagazine.com
(being written/started March 2011)
hamelectronicsmagazine.com
(being written/started March 2011)
LINK TO my old web site (still active for a few
months...until this one fully takes over)
www.earlandrews.com
73 earl ve3ab
months...until this one fully takes over)
www.earlandrews.com
73 earl ve3ab
FT221 mods courtesy of Dani IW2EFF.. link to be
developed..as the article gets written up.
developed..as the article gets written up.