The ultimate in double

density adapter units

This is a Tuc's Workbench remix of the LNDoubler 5/8 (Also known at "The Switch") from the LNW Research Corp. 

From the original description -

The LNDOUBLER 5/8 switches your TRS80 MODEL I or LNW80 computer into the most versatile computer you can own. Whether you want single sided, double sided, single or double density,5 or 8 inch disk operation,any combination of disk storage is possible with the LNDOUBLER 5/8. Each of your present 40 track single sided disk drives will store up to 184,320 bytes (formatted)-thats an 80% increase! The LNDOUBLER 5/8 even allows you to BOOT from an 8" system disk with a flip of a switch.The  LNDOUBLER 5/8 is compatible with all software available for 5" single and double density,8" single and double density written for the TRS80.

The LNDOUBLER 5/8 is easy to install.There are no traces to cut,no soldering or wiring.Just unplug the floppy controller IC (FD1771) from your interface, install the FD1771 into the LNDOUBLER 5/8, and just plug the LNDOUBLER 5/8 into the
interface.In just a few minutes you'll be enjoying your computer as never before.
The LNDOUBLER 5/8 is the most technically advanced, tested and reliable double density board you can own.The LNDOUBLER 5/8 has more features, more capabilities, and more software support than any product of it's kind.

FEATURES

* RELIABLE OPERATION GUARANTEED WITH ALL 5.25" and 8" DISK DRIVES
* SINGLE AND DOUBLE DENSITY OPERATION
* 5.25" AND 8" IN ANY MIX
* READ MODEL I,II,III DISKS
* 5.25" AND 8" SYSTEM DISKS
* ANALOG PHASE LOCK LOOP DATA SEPARATION
* PRECISION WRITE PRECOMPENSATION
* REGULATED SUPPLY FOR VCO AND ALIGNMENT CIRCUITS
* GUARANTEED OPERATION WITH ALL TRS8Ø EXPANSION INTERFACE UNITS
* ALL GOLD CONTACTS
* GUARANTEED OPERATION AT 4.Ø MHZ CPU SPEED
* COMPATIBLE WITH ALL SINGLE, DOUBLE AND 8" DRIVE SOFTWARE
* EASY INSTALLATION
* FIVE INCH DISK STORAGE INCREASED TO :

• 161,280 bytes- 35 track ss/dd
• 322,560 bytes- 35 track ds/dd
• 184,320 bytes- 40 track ss/dd
• 368,640 bytes- 40 track ds/dd
• 368,640 bytes- 80 track ss/dd
• 737,280 bytes- 80 track ds/dd

* EIGHT INCH DISK STORAGE INCREASED TO:

• 335,104 bytes- 77 track ss/sd
• 670,208 bytes -77 track ds/sd
• 591,360 bytes -77 track ss/dd
• 1,182,720 bytes -77 track ds/dd

ss: single sided         sd: single density       ds: dual sided       dd: double density

MEDIA AND DRIVE REQUIREMENTS

Since the LNDOUBLER 5/8 will work with virtually any drive and any media, it may be tempting to use (for example) low cost single density single sided 35 track diskettes with 80 track, double density double sided drives. On the other hand, experimentation to find out which diskettes work the best, may lead to the conclusion that any diskettes will work. For this reason we at LNW RESEARCH make the following suggestions:

1.Use double density rated disk drives. Single density drives may work, but the proper operation in double density cannot be guaranteed for the life of the drive.
2.Use diskettes rated according to their use
3.Check diskettes for wear periodically
4.Clean and align your disk drive (s) according to the
manufacturer's recommendations.

***NOTE*** - These units are NOT just plug and play. Given their nature, they need to be adjusted. You will need -

• Digital voltmeter 1% accuracy >1megohm input impedance 
• Frequency counter .1% accuracy >1k ohm input >5mhz
• Oscilloscope >15mhz bandwidth ,triggered

If you do not own these, or do not feel comfortable using them, PLEASE DO NOT ORDER.  We are not pre-adjusting them. I'd rather miss out a sale than have you unhappy. 

There are 2 models. If you already own a FD1791 or compatible 40 pin chip, you don't need to pay the added expense of receiving another. If you don't, then order with the FD1791 or compatible chip.

Order today!