Tapeheads Tape, Audio and Music Forums
Universal Capstan Motor

Go Back   Tapeheads Tape, Audio and Music Forums > Tape, Taping and Tape Machines > Reel To Reel

Reel To Reel All discussions pertaining to reel to reel decks. These include general usage, recording, playback, and service questions. For subjects related to tape itself, see the Open Reel subforum under this one. Obscure service subjects that don't quite fit go in the Help and Do It Yourself subforum.

Donate to Tapeheads!
Reply
 
Thread Tools Display Modes
  #1  
Old 11-08-2008, 11:05 AM
TheReeler's Avatar
TheReeler TheReeler is offline
Reeling and railing!
 
Join Date: Aug 2008
Location: Barcelona
Posts: 1,195
Changing Pioneer RT-707 direction lamps for leds

Today I was working a Pioneer RT-707, putting some grease in the capstan motor and adjusting the fly wheel when both direction lamps burned. It's rare that both lamps burn at the same time, but I think that this happened because they were in their last hours, and after manipulated the deck, putting it up, down... etc, finally the filaments broke.

Fortunatelly I had some leds left at home, so I began to replace both direction lamps with leds. The voltage to the lamps is about 26VDC, so a balast resistor is needed in serial with each led. I used 5mm width leds, that enter perfectly in the hold.

In a first time I tried a 1.3Kohms. 1/4 watt. After testing, it got too hot, so I tried a 2.2 Kohms. and with more wattage. Tested that first one led with it and all was working well.

Here is the procedure I followed to change the direction lamps with leds.

**Click in the images to watch the big version


1- Remove the deck cover. Four philips screws in each side and three more in the upper.


2- Remove the front panel. Two philips screws and three more in the bottom. Remove the pots knobs of MIC and LINE controls. Also the pinch control knob. To remove the front panel now, both pinch roller must be pushed up manually and with care, pull the panel.


3- Both direction lamps are in a small black socket. To remove it, unscrew the two philips screws.




Each lamp is inside his hole and can be removered simply pulling the lamp from their wires.





4- Solder the balast resistor to the cathode of the led (in the image is shown the first resistor that I tried). Use a simple tester to know which wire will go to the cathode and which one to the anode.




5- Put the led inside the original socket






6- Solder the wires to the led and the balast resistor



Here is another pic with the final balast resistor selected, 2.2 KOhms.




7- Solder the other direction led.


8- Test both direction leds.






9- Put some electric tape in the chasis where will be hold the leds socket, to make a dielectric layer so that nothing wrong happens if some wire of the new leds touch the bottom part of the socket once it has been put in its original place




10- Put the leds socket in its place with the two philips screws and test the work







11- Put the front face and the cover in their original places.


That's all folks!
  #2  
Old 11-08-2008, 11:26 AM
4tified's Avatar
4tified 4tified is offline
Ferrochrometal
 
Join Date: Oct 2008
Location: TX (U.S.A)
Posts: 800
Well, I don't have a pioneer RT-707, but I just wanted to say very nice step-by-step guide, with pics even! Anyone should be able to do this.
__________________

  #3  
Old 11-08-2008, 12:51 PM
Scorpion8's Avatar
Scorpion8 Scorpion8 is offline
Cassetticus Maximus
 
Join Date: May 2008
Location: SouthEast AK
Posts: 17,134
Very nice, as changing lamps to LEDs is almost universal in methodology. Think we'll make this one a sticky.
__________________
Moderator; Sony cassette spoken here...
Retired USN

Crush your enemies. See them driven before you. Hear the lamentations of their women.
  #4  
Old 11-08-2008, 01:05 PM
gamve's Avatar
gamve gamve is offline
Total Tape Nut
 
Join Date: Jul 2008
Location: Tasmania, Australia
Posts: 2,027
Nice work Reeler. Another one for the maintenance reference section
  #5  
Old 04-23-2009, 01:16 PM
koseltri's Avatar
koseltri koseltri is offline
The reel deal?
 
Join Date: Apr 2009
Location: Oregon
Posts: 143
Perfect! The forward lamp on my 'new' 707 is out. Soon as I'm back to normal (wrist surgery yesterday), I'll do it up. Thanks for the pix.
  #6  
Old 06-03-2011, 10:32 AM
Big Bill Big Bill is offline
TapeHeads.Net Member
 
Join Date: Jun 2011
Posts: 13
Very helpful!

Thanks for the post, it helped tremendously. I found good results using the 2.2K resistors and 5mm green LEDs (20mA 40mcd). Radio Shack part number# 276-0022.

Thanks again, Bill!
  #7  
Old 06-03-2011, 11:52 AM
retrokeeper's Avatar
retrokeeper retrokeeper is offline
Long Live Magnetic Medium
 
Join Date: Jun 2008
Location: Washington State
Posts: 3,089
I'll do mine when I get around to checking out my 707..thanks for the info & instructions! Rob
  #8  
Old 09-12-2012, 05:56 AM
jleon92f's Avatar
jleon92f jleon92f is offline
Magnetic Profiler
 
Join Date: Sep 2012
Location: AZ
Posts: 183
Nice repair procedure, I will do this when I go to change my lamps, one is burnt out now.

Thanks,
John.
__________________
Vintage System, Marantz 2250B, Yamaha K-2000, Mitsubishi DT-40S, JVC QL-5, KLH 911B speakers.
  #9  
Old 08-07-2014, 10:55 AM
kevman kevman is offline
TapeHeads.Net Member
 
Join Date: May 2014
Posts: 31
anyone know the specs for that resistor? how much wattage ? I see 1/2 , 1 and 2 Watt resistors at Radio Shack.
  #10  
Old 08-07-2014, 11:51 AM
Skywavebe's Avatar
Skywavebe Skywavebe is offline
Skywave Tape Deck Repair
 
Join Date: Jul 2008
Location: Bensenville, IL
Posts: 12,958
You just need to know some of ohms law to figure this out. I did one out of necessity not too long ago and I used 3mm LED that were expanded with heat shrink tubing to make then stick in the holders. my purpose is to get the lamps up more forward where the original filaments were. Perhaps this
was no matter but my resistors were like 1.2K. Of course it all depends on what LED you are using and it's maximum voltage and I rating.
I use the Vs- Vled max to get the resistor voltage drop required and 26 Vdc was present and Led max was 2.7V so 23.2 was the drop and error on the side of better the LED could draw 20 mA so 23.3/.020 is 1165 ohms. So I selected a 1.2K resistor that was 1/2 watt. Now the power calc- the
P=I^2 x R so .0004 X 1200=.48W so the 1/2 watt resistor should do. I put the resistor in line with the wires to the LED and covered the bare areas with heat shrink, The resistor itself is not conductive and the did not get that warm. They were plenty bright and these were the White point source LED I bought for meter lighting experiments a while back by the 100 quantity on E bay. I stock White, Blue, Yellow, and Red in 10mm, 5mm and 3mm LED's. it is good to be prepared when you need to do a project like this. Yes, I have thousands of resistors is stock too all values.

There are color lenses in the buttons and so the white will work as well as the green or maybe be brighter.
__________________
Best regards,

Sam Palermo, BSEE and ProSquad Member
Skywave Tape Deck Repair- Chicago area
(630)616-0932 Office/ Email:skywavebe@sbcglobal.net
Past Teac/Tascam Lead Service Technician at Chicago Factory Service still doing repairs.
http://s609729863.onlinehome.us/tape...uipment-repair
Now accepting MC, Visa, Amex & Discover Cards!
  #11  
Old 08-07-2014, 02:14 PM
kevman kevman is offline
TapeHeads.Net Member
 
Join Date: May 2014
Posts: 31
Thanks SAM, so I think I got it down

My LED specs are Forward voltage: max 3.0, IF=20mA

So that transalates to 1150 ohms of resistance and power .46w

So a 1.2k Ohm resistore with 1/2 power will do it.

Thanks!
  #12  
Old 08-07-2014, 06:38 PM
kevman kevman is offline
TapeHeads.Net Member
 
Join Date: May 2014
Posts: 31
For anyone that wants to do this here are the parts I picked up from Radio Shack

LED 2PK:
Item# 226-022
RadioShack 5mm Green LED

Resistor 5PK:
Item # 271-1120
1.5K ohm 1/2W 5% Carbon Film Resistor pk/5

These specs seem to mate together based on the calculations. I'll report back when I get to test this out.
  #13  
Old 08-09-2014, 09:50 AM
kevman kevman is offline
TapeHeads.Net Member
 
Join Date: May 2014
Posts: 31
I know that the Resistor must get soldered to the cathode side of the LED. But on the RT707 is there a polarity to be considered when attaching the LED to the unit ?
  #14  
Old 03-02-2015, 10:00 AM
JVRaines JVRaines is offline
Serious Tapehead
 
Join Date: Feb 2015
Posts: 221
Quote:
Originally Posted by kevman View Post
I know that the Resistor must get soldered to the cathode side of the LED. But on the RT707 is there a polarity to be considered when attaching the LED to the unit ?
Yes, absolutely. If you connect it backwards, the LED won't light. Use a voltage tester to determine which wire is positive and connect it to the anode (long leg, round side) of the LED. The resistor can go on either side.

I just performed this repair with some 3 mm white LEDs from Parts Express and a 2.2 KΩ 1/2 w resistor. They're rated 1500 mcd, so are still quite bright at 10 mA and the resistors stay cool.

Forgot to mention that the lamps are ground-switched, so I put a single resistor up at the connector board and used just one of the positive wires in a common-anode arrangement.

Last edited by JVRaines; 03-02-2015 at 04:15 PM.
  #15  
Old 02-03-2017, 07:56 PM
Sawtooth's Avatar
Sawtooth Sawtooth is offline
Lover of all things TECH!
 
Join Date: Jan 2017
Location: Canada, eh?
Posts: 383
Nice pics, good job
  #16  
Old 02-05-2017, 06:26 PM
ursman's Avatar
ursman ursman is offline
The NICE PRICE!
 
Join Date: Dec 2015
Location: Parker, CO
Posts: 488
Just did this mod tonight and it worked perfectly. I got a little different and changed them out to blue in keeping with the Pioneer flourascan theme. Looks awesome. Thanks for the write up!
__________________
__________________________________________
Receiver: Pioneer SX-1050 EQ: Sansui SE-9 R2R: Sony TC-458, Pioneer RT-707, Cassette: Nakamichi RX-303, Pioneer CT-F1250, CT-F900, CT-M6R, Turntable: Pro Ject Perspex SB with Sumiko BPS EVO III, Pre-amp Pro Ject Tube Box S MD: Sony MDS-JE440 NAD: Pioneer Elite C-50
Digital Media can byte me!
  #17  
Old 02-05-2017, 06:48 PM
Skywavebe's Avatar
Skywavebe Skywavebe is offline
Skywave Tape Deck Repair
 
Join Date: Jul 2008
Location: Bensenville, IL
Posts: 12,958
I wanted to do a follow up on my comment in that the Resistors attached to the LED's are difficult to do because of space limitations. What I did find is that there are some wire wrap posts that the wires go to on the top board and that is a much better place to mount resistors that are to get warm.
If the calculation says .46W then the correct engineering to do is put in a 1 watt resistor OR double the resistance value to use and connect two 1/2 W resistors in Parallel- thus same ending resistance and 1 watt dissipation. Use heat shrink to prevent the resistor from touching other vertical pins.
The place the resistor goes in does not matter as the same current will flow in the cathode or anode end of the LED circuit. The polarity of the LED must be correct though. Good to test all this stuff before closing it up.

Also do not use the maximum forward voltage in the calculations but it is wise and common to use 70-80% of the max voltage and then that will still be bright enough even with high output 3 mm types.

The lamps go out at the same time due to vibration as the filaments are
extremely fragile after all these years- it is probably a good practice to replace them now every time.
__________________
Best regards,

Sam Palermo, BSEE and ProSquad Member
Skywave Tape Deck Repair- Chicago area
(630)616-0932 Office/ Email:skywavebe@sbcglobal.net
Past Teac/Tascam Lead Service Technician at Chicago Factory Service still doing repairs.
http://s609729863.onlinehome.us/tape...uipment-repair
Now accepting MC, Visa, Amex & Discover Cards!
  #18  
Old 02-05-2017, 07:09 PM
ursman's Avatar
ursman ursman is offline
The NICE PRICE!
 
Join Date: Dec 2015
Location: Parker, CO
Posts: 488
Now you tell me Sam! Lol. I didn't even think about the position of the resistor. That would have saved me a bit of wire massaging. Next deck I do I will remember this little useful fact.
__________________
__________________________________________
Receiver: Pioneer SX-1050 EQ: Sansui SE-9 R2R: Sony TC-458, Pioneer RT-707, Cassette: Nakamichi RX-303, Pioneer CT-F1250, CT-F900, CT-M6R, Turntable: Pro Ject Perspex SB with Sumiko BPS EVO III, Pre-amp Pro Ject Tube Box S MD: Sony MDS-JE440 NAD: Pioneer Elite C-50
Digital Media can byte me!
  #19  
Old 05-29-2017, 04:52 PM
390FE's Avatar
390FE 390FE is offline
Serious Tapehead
 
Join Date: Jan 2009
Location: Western NY
Posts: 5,232
As an fyi if you source and get a true 12v LED (Note: true 12v LED's have NO external dropping resistor as it is all on the chip dye in the LED lens) this will reduce the wattage requirements on the dropping resistor thus making fitting the resistor some place a bit easier as it will be smaller in size.

Hope this helps.
  #20  
Old 05-29-2017, 05:05 PM
Skywavebe's Avatar
Skywavebe Skywavebe is offline
Skywave Tape Deck Repair
 
Join Date: Jul 2008
Location: Bensenville, IL
Posts: 12,958
This may be correct but most Technician have piles of LED's on hand but not many 12 V ones. Plus if they ever go out and you do not remember that 12 V lamps are in then the regular type LED's will burn out fast as they might not be 12 V types. LED's do last a long time but they do burn out if a lot of hours are put to them. They are transistor junctions and we know that after 30-40 years we are finding bad transistors once in a while unless you have an Akai where it is more often than not.
Which ever way you want to do it.
__________________
Best regards,

Sam Palermo, BSEE and ProSquad Member
Skywave Tape Deck Repair- Chicago area
(630)616-0932 Office/ Email:skywavebe@sbcglobal.net
Past Teac/Tascam Lead Service Technician at Chicago Factory Service still doing repairs.
http://s609729863.onlinehome.us/tape...uipment-repair
Now accepting MC, Visa, Amex & Discover Cards!
Reply


Would you like to see your company or site here?  CONTACT US
For more Tapeheads affiliates and links, see the Links and Resources page.


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Belt Changing Example Pioneer CT-F1250 gamve STICKY - Cassette Decks and Tapes 15 07-08-2016 05:36 PM
pioneer rt 707 directional lamps tmott714 Reel To Reel 5 06-26-2014 05:09 AM
Lamps to LED conversion on a Pioneer RT-707 R-2-R Reel To Reel 6 01-21-2013 09:46 AM
Pioneer CT-F1250, CT-F850, TX-7800, SA-8800 - Need direction nardeep Cassette 1 10-22-2011 03:10 PM
Pioneer SA 6500 need direction. Larry N Help and Do It Yourself 0 04-22-2011 12:19 PM


All times are GMT -7. The time now is 03:48 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright ©2016, Tapeheads.Net. All rights reserved, no use of any element incorporated into this site without express written permission.