Here are the steps to downgrade any 3.50 PSP to 1.50:
降级步骤
1 - If you have a 3.50 PSP skip to step 6
如果你的PSP已经是3.50的固件，请直接到第6步。
2 - Download 3.50 update from here: http://dl.qj.net/PSP-Firmware-3.50-(North-America)-PSP/pg/12/fid/13840/catid/163
下载3.50固件 http://dl.qj.net/PSP-Firmware-3.50-(North-America)-PSP/pg/12/fid/13840/catid/163
3 - Unzip and place the file in <pspdrive>:/PSP/GAME/UPDATE
解压并放入记忆棒的 <pspdrive>:/PSP/GAME/UPDATE 文件夹内
4 - On the PSP, run the 3.50 update from the memory stick under the Game menu.
在PSP上运行3.50的升级程序
5 - Delete <pspdrive>:/PSP/GAME/UPDATE
升级完成后删除3.50的升级程序
6 - Copy the contents of the folder MS_ROOT from the 3.50 downgrader ZIP to
the memory stick
复制降级包中的MS_ROOT文件夹内的PSP文件夹到记忆棒根目录（最好事先把记忆棒先格式化下，但不是必须。）
7 - Unzip the 1.50 update to a temporary folder. Rename the EBOOT.PBP to
UPDATE.PBP and copy it to <pspdrive>:/PSP/GAME/UPDATE/ . DO NOT
OVERWRITE PSP/GAME/UPDATE/EBOOT.PBP!
解压1.50的升级程序到一个临时文件夹，并把EBOOT.PBP 更名为UPDATE.PBP，
然后复制到<pspdrive>:/PSP/GAME/UPDATE/
不要覆盖 PSP/GAME/UPDATE/EBOOT.PBP文件 切记要改名
8 - Load Lumines and press x to start the game
运行音乐方块游戏
9 - The screen will clear to black and fill with a light blue colour, then
the PSP will reset itself
屏幕将变黑然后变成蓝屏，随后PSP将自动复位
10 - Check that HEN is running by going to system settings, then to
"System Information" and it should show up as system version
350 HEN
检查系统信息 中的系统版本是否是 350 HEN
11 - If it is showing up as HEN then go to the memory stick and
run the x.yz update
如果上步没有出错，运行游戏下的 x.yz update 程序
12 - If you have an unpatched TA-082 or higher motherboard, you will be
prompted to allow the downgrader to patch your motherboard so it
can be safely downgraded. The downgrader will not let you proceed
without patching, if your motherboard requires it.
如果你是一个TA-082或者更高级的主办，你将被程序引导为你的主板打补丁来更安全的降级
13 - Before the downgrader does anything to your PSP it will ask
for you to agree to what it is doing, if you no longer want to
continue press the Right Shoulder Button (R-TRIGGER).
在降级之前，程序将询问你是否确定要降级，如果不同意，请按R-TRIGGER
14 - Once you have agreed to start the downgrade do not unplug the
PSP, or try and restart it
一旦你同意降级，请不要动任何案件或者复位PSP
15 - Once finished the PSP will ask you to press X, and reset itself
降级完成后程序将要求你按X键来从起PSP
16 - If it comes up saying that the settings are corrupt, press x
to continue, this will mean you will need to re-enter the
settings for network connections into your PSP, otherwise go to
step 18
如果提醒设置破损，按X继续，这意味着你将从新设置你的PSP 网络连接设置。
如果没有提示 直接进入18步
17 - Load the included NetConfigBackup application in your PSP, and select to
restore, this will take the backup that was done of the network config
that was done automatically during the downgrade.
运行NetConfigBackup 程序在PSP上，选择 restore 来修复 你的PSP网络设置
18 - All done now :-) Hopefully you now have a 1.50 PSP. Enjoy it responsibly.
所有降级步骤完成，您现在已经有了一个固件版本为1.50的PSP，Enjoy it 。
